Jason Klaus, who is 38, was charged on the weekend in the slayings of his parents, Gordon and Sandra Klaus, and his sister Monica Klaus.
RCMP say the three were killed in a house fire in Castor last December.
Klaus, also from Castor, and his friend Joshua Frank are both charged with first-degree murder and arson.
The appeared in court via closed-circuit TV and are to remain in custody until their next appearance in Red Deer on Sept. 17.
Klaus kept his head bowed as the charges were read and Frank showed no emotion.
Some family members were in court and requested privacy.