Jason Custer made his pleas during an arraignment Thursday in Cheyenne County District Court in Sidney.
Custer is accused of fatally shooting Adam McCormick on Nov. 3 in Sidney. Authorities have said they think the two men were arguing about $160 in drug money.
Custer fled Sidney to Big Springs, where he was arrested later that day at a motel.
Custer remains in custody, pending $1 million bail. His next hearing is scheduled for Jan. 8.