David Jones tallied the decisive goal at 2:35, just 1:35 after Colorado's Gabriel Landeskog scored to tie the game 1-1.
Landeskog, who took six shots in the game, fired a wrist shot into the net a 1:00 of the third period. Jones followed up with power-play goal assisted by Peter Stastny, and PA Parenteau added an insurance goal at 8:16.
Semyon Varlamov provided 28 saves for the Avalanche, who won their home opener and extended their winning streak against the Kings to five games.
Kyle Clifford staked Los Angeles to a 1-0 lead at 15:52 of the first period, but the Kings could not get past Varlamov again. Colorado out-shot Los Angeles 31-29.
Jonathan Quick stopped 19 shots in the first two periods but gave up three goals in a dozen shots in the third.