'Star Trek' Actor Walter Koenig Dead at 90

Walter Koenig -- the TV star best known for playing Ensign Pavel Chekov in the original "Star Trek" series -- has died ... TMZ has learned.

The late actor's rep tells us ... Walter's daughter, Danielle, and his niece were by his side when he died of old age at his home in North Hollywood on Sunday.

The rep noted his enormous talent -- including his recent win at the 2026 Independent Shorts Awards for his performance in the film "Mr. Fleischmann" -- as well as his larger legacy.

At conventions, the rep says Walter "shared his kindness, wit, and appreciation with everyone fortunate enough to meet him. He understood what Star Trek meant to people and embraced the community that grew around it."

The rep expressed condolences to Walter's loved ones and fans ... before adding, "Thank you, Walter, for the memories, the inspiration, and for boldly going where few have gone before."

Walter began acting onscreen in the early 1960s, appearing in bit roles on shows like "Gidget" and "I Spy" before landing the role of Chekov, which he played on 36 episodes of "Star Trek."

He later reprised his role in "Star Trek: The Motion Picture," "Star Trek II: The Wrath of Khan," "Star Trek III: The Search for Spock" and several other sequels.

Walter's credits also include "Babylon 5," "Columbo," and "Futurama" ... among many others.

He was predeceased by his son, Andrew Koenig, who died by suicide in 2010.

We last caught up with Walter in 2009 ... when we asked him about the secret to a successful marriage. He and his wife Judy were married for nearly 60 years ... until she passed in 2022.

He was 90.