The incident occured on the 500 block of Carruthers Court around 7:30 p.m.
Investigators say Pomona police officers were responding to a family disturbance, when a man holding a large kitchen knife met them.
The man allegedly refused officers orders to drop the knife and got aggressive, resulting in the shooting.
The suspect was transported to a nearby hospital, where he was pronounced dead.
No one else was injured.
The Los Angeles County Sheriff's Department is investigating the shooting.