Stephen "tWitch" Boss, the famed DJ on Ellen DeGeneres' talk show, is dead ... and TMZ has learned it appears to be a suicide.

Law enforcement sources tell us Stephen's wife Allison Holker ran into an LAPD station Tuesday, and she was frantic because she said Stephen had left home without his car -- something that was not like him at all.

We're told, a short time later -- around 11:15 AM -- paramedics got a call for a medical emergency at an L.A. hotel ... and they found Stephen there, dead from an apparent self-inflicted gunshot wound. He was pronounced dead at the scene.

Holker tells TMZ, "Stephen lit up every room he stepped into. He valued family, friends and community above all else and leading with love and light was everything to him."

She continues, "He was the backbone of our family, the best husband and father, and an inspiration to his fans. To say he left a legacy would be an understatement, and his positive impact will continue to be felt. I am certain there won’t be a day that goes by that we won’t honor his memory."

Concluding, "Stephen, we love you, we miss you, and I will always save the last dance for you."

Stephen started DJing on Ellen's show in 2014, and was with her until the show ended in May 2022. He had become an executive producer on the show in 2020.

He really got his big break in showbiz in 2008, when he was runner-up on "So You Think Can Dance."

He went on to do some acting, landing several roles where he could show off his dance skills. Stephen played Jason in the 'Step Up' movie franchise, and he was also in "Magic Mike XXL."

The last time our photogs got him out around L.A. was back in September, and he talked to us about life after 'Ellen' ... sounding pretty happy to have more time with his family.

Stephen hosted several reality shows, like "The Real Dirty Dancing" -- which aired on FOX earlier this year -- and he and Allison teamed up for "Disney's Fairy Tale Weddings" on Disney+.

A statement from FOX Entertainment, 19 Entertainment and Dick Clark Productions, reads, "We will always remember Stephen “tWitch” Boss for the light and joy he brought into our lives and into the hearts of so many. This tragic, painful loss of such a radiant, inimitable talent and beloved friend is immeasurable beyond words, and we grieve alongside his family, loved ones and fans. “tWitch,” we will miss you dearly.”

tWitch and Allison met on the all-star season of 'SYTYCD' -- they were both competing -- and they got married in 2013. Allison and Stephen had just celebrated their 9-year anniversary this past Saturday.

They had 3 kids. Stephen was 40 years old.

RIP

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