Lars Magnus Ericsson (May 5, 1846 - December 17, 1926) was a Swedish inventor and founder of telephone equipment manufacturer Ericsson (incorporated as Telefonaktiebolaget LM Ericsson ).

Lars Magnus was born in Värmskog , Wermelandia and grew up in the small village of Wegerbol , between Karlstad and Arvika. At the age of twelve his father died, and he had to start working as a miner. He worked until he had money enough to leave the village and move to Stockholm in 1867. He then worked for six years for an instrument maker named Öllers & Co. who mainly created telegraph equipment. Because of his skills, he was given two state scholarships to study instrument making abroad between 1872 and 1875. One of the companies he worked at was Siemens & Halske.

Upon his return to Sweden in 1876 he founded a small mechanical workshop together with his friend Carl Johan Andersson who had also worked at Öllers & Co.. This workshop was actually a former kitchen of some 13m² situated at Drottninggatan 15 in the most central part of Stockholm. Here, he started telephone work by analyzing Bell company and Siemens telephones and creating his own copies in their image. It was not until they started cooperating with Henrik Tore Cedergren in 1883 that the company would start to grow into the Ericsson corporation as we know it today.

More of the history of the company can be found under the Ericsson entry.

In the year 1900 Lars Magnus retired from Ericsson at the age of 54. He kept his shares in the company until 1905 and then sold them all.

He is said to have been a demanding person, and disliked any direct publicity about his person and did not wish to be idolized. However he was deeply respected by his employees. He was always a skeptic and cautious in business. He was also somewhat opposed to patents, as many of the products he made would not have been possible to do if the patent legislation had been overly effective. When his phones were copied by Norweigan companies he did not care, as his phones were in turn largely copied from Siemens. He initially did not believe in a mass market for telephones, and saw it as a toy for the leisure class.

After his death in 1926 he was buried at Hågelby gård in Botkyrka. At his explicit request, there is no headstone marking his grave.