Michael Ronen, Goldman Sachs Group Inc.'s co-chief operating officer of the global technology, media and telecommunications group, is leaving the firm to join Masayoshi Son's planned $100 billion SoftBank Vision Fund.

Ronen will join the fund later this year and move from New York to its base in San Carlos, California, according to a statement Tuesday. His retirement from Goldman Sachs was announced in a separate internal memo that was seen by Bloomberg.

Ronen has known Son for many years and was intrigued by the opportunity to work on the world's largest private equity fund, according to a person familiar with the matter, asking not to be named because the matter is private. Ronen has worked on many large technology, media and telecom deals in recent years, including SoftBank Group Corp.'s deal for majority control of Sprint Corp. in 2013. He has been involved with putting together the Vision Fund this year.