In 1938, Lee Byung-chul (1910–1987) of a large landowning family in the Uiryeong county moved to nearby Daegu city and founded Samsung Sanghoe (삼성상회, 三星商會). Samsung started out as a small trading company with forty employees located in Su-dong (now Ingyo-dong). It dealt in dried-fish, locally-grown groceries and noodles.

The company prospered and Lee moved its head office to Seoul in 1947. When the Korean War broke out, he was forced to leave Seoul.

When the Korean War broke out, he was forced to leave Seoul. He started a sugar refinery in Busan named Cheil Jedang.

In 1954, Lee founded Cheil Mojik and built the plant in Chimsan-dong, Daegu. It was the largest woollen mill ever in the country.

In 1980, Samsung acquired the Gumi-based Hanguk Jeonja Tongsin and entered telecommunications hardware. Its early products were switchboards. The facility was developed into the telephone and fax manufacturing systems and became the center of Samsung's mobile phone manufacturing. They have produced over 800 million mobile phones to date. The company grouped them together under Samsung Electronics in the 1980s.

After Lee, the founder's death in 1987, Samsung Group was separated into four business groups—Samsung Group, Shinsegae Group, CJ Group and the Hansol Group.

The Samsung Medical Center was founded on 9 November 1994, under the philosophy of "contributing to improving the nation's health through the best medical service, advanced medical research and development of outstanding medical personnel". The Samsung Medical Center consists of a hospital and a cancer center. The hospital is located in an intelligent building with floor space of more than 200,000 square meters and 20 floors above ground and 5 floors underground, housing 40 departments, 10 specialist centers, 120 special clinics and 1,306 beds.The 655-bed Cancer Center has 11 floors above ground and 8 floors underground, with floor space of over 100,000 square meters. SMC is a tertiary hospital manned by approximately 7,400 staff including over 1,200 doctors and 2,300 nurses. Since its foundation, the Samsung Medical Center has successfully incorporated and developed an advanced model with the motto of becoming a "patient-centered hospital", a new concept in Korea.

Samsung Techwin acquired German camera-maker Rollei in 1995. Samsung (Rollei) used its optic expertise on the crystals of a new line of 100% Swiss-made watches, designed by a team of watchmakers at Nouvelle Piquerez S.A. in Bassequort, Switzerland. Rolex's decision to fight Rollei on every front stemmed from the close resemblance between the two names and fears that its sales would suffer as a consequence. In the face of such a threat, the Geneva firm decided to confront. This was also a demonstration of the Swiss watch industry's determination to defend itself when an established brand is threatened. Rolex sees this front-line battle as vital for the entire Swiss watch industry. Rolex has succeeded in keeping Rollei out of the German market. On 11 March 1995, the Cologne District court prohibited the advertising and sale of Rollei watches on German territory.

Samsung was ranked 221 on the 1995 Fortune Global 500 list.

Samsung was ranked 120 on the 1996 Fortune Global 500 list.

Samsung was ranked 124 on the 1997 Fortune Global 500 list.

Samsung was ranked 142 on the 1998 Fortune Global 500 list.

Samsung was ranked 207 on the 1999 Fortune Global 500 list.

Samsung was ranked 131 on the 2000 Fortune Global 500 list.

Samsung was ranked 92 on the 2001 Fortune Global 500 list.

Samsung was ranked 105 on the 2002 Fortune Global 500 list.

Samsung was ranked 59 on the 2003 Fortune Global 500 list.

Samsung was ranked 55 on the 2004 Fortune Global 500 list.

Samsung grew to be the world's largest manufacturer of liquid-crystal display panels. Sony, which had not invested in large-size TFT-LCDs, contacted Samsung to cooperate, and, in 2006, S-LCD was established as a joint venture between Samsung and Sony in order to provide a stable supply of LCD panels for both manufacturers. S-LCD was owned by Samsung (50% plus one share) and Sony (50% minus one share) and operates its factories and facilities in Tangjung, South Korea.

Samsung was ranked 39 on the 2005 Fortune Global 500 list.

Samsung was ranked 46 on the 2006 Fortune Global 500 list.

Samsung was ranked 46 on the 2007 Fortune Global 500 list.

Samsung was ranked 38 on the 2008 Fortune Global 500 list.

Samsung was ranked 40 on the 2009 Fortune Global 500 list.

Samsung was ranked 32 on the 2010 Fortune Global 500 list.

On 19 October 2011, Samsung companies was fined €145,727,000 for being part of a price cartel of ten companies for DRAMs which lasted from 1 July 1998 to 15 June 2002.

As of 26 December 2011, it was announced that Samsung had acquired the stake of Sony in S-LCD.

Samsung was ranked 22 on the 2011 Fortune Global 500 list.

On 9 May 2012, mSpot announced that it had been acquired by Samsung Electronics with the intention of a cloud based music service. The succeeding service was Samsung Music Hub.

On 24 August 2012, nine American jurors ruled that Samsung Electronics had to pay Apple $1.05 billion in damages for violating six of its patents on smartphone technology. The award was still less than the $2.5 billion requested by Apple. The decision also ruled that Apple did not violate five Samsung patents cited in the case. Samsung decried the decision saying that the move could harm innovation in the sector. It also followed a South Korean ruling stating that both companies were guilty of infringing on each other's intellectual property.

In December 2012, Samsung announced that it had acquired the privately held storage software vendor NVELO, Inc., based in Santa Clara, California. NVELO will become part of Samsung's R&D operations, and will focus on software for intelligently managing and optimizing next-generation Samsung SSD storage subsystems for consumer and enterprise computing platforms.

Samsung was ranked 20 on the 2012 Fortune Global 500 list.

In January 2013, Samsung announced that it has acquired medical imaging company NeuroLogica, part of the multinational conglomerate's plans to build a leading medical technology business. Terms of the deal were not disclosed.

Samsung was ranked 14 on the 2013 Fortune Global 500 list.

On 14 August 2014, Samsung acquired SmartThings, a fast-growing home automation startup. The company isn't releasing the acquisition price, but TechCrunch reported a $200 million pricetag when first caught word of the deal in July 2014.

On 19 August 2014, Samsung said it had acquired U.S. air conditioner distributor Quietside LLC as part of its push to strengthen its "smart home" business. A Samsung Electronics spokesman said the South Korean company acquired 100 percent of Quietside, but declined to elaborate on the price or other details.

3 November 2014, Samsung announced it had acquired Proximal Data, Inc., a San Diego, California-based pioneer of server-side caching software with I/O intelligence that work within virtualized systems.

Samsung was ranked 13 on the 2014 Fortune Global 500 list.

On 18 February 2015, Samsung acquired U.S.-based mobile payments firm "LoopPay" - This allows Samsung in smartphone transactions.

Samsung was ranked 13 on the 2015 Fortune Global 500 list.

On 2 August 2016, Samsung Electronics unveiled the Galaxy Note7 smartphone, which went on sale on 19 August 2016.

On 5 October 2016, Samsung announced it had acquired Viv, a company working on artificial intelligence.

However, in early September 2016, Samsung suspended sales of the phone and announced an informal recall. This occurred after some units of the phones had batteries with a defect that caused them to produce excessive heat, leading to fires and explosions. Samsung replaced the recalled units of the phones with a new version; however, it was later discovered that the new version of the Galaxy Note 7 also had the battery defect. Samsung recalled all Galaxy Note7 smartphones worldwide on 10 October 2016, and permanently ended production of the phone the following day.

Samsung was ranked 13 on the 2016 Fortune Global 500 list.

Samsung was ranked 15 on the 2017 Fortune Global 500 list.

Samsung was ranked 12 on the 2018 Fortune Global 500 list.