Kempe, who missed the Kings’ 3-2 loss to the Buffalo Sabres on Saturday because of an undisclosed injury, got his fifth NHL hat trick.
Artemi Panarin had four assists, and Quinton Byfield scored twice on the power play for the Kings (5-7-2), who have won two of three to start a seven-game homestand. Darcy Kuemper made 30 saves.
Macklin Celebrini and Ivar Stenberg each scored on the power play for the Sharks (7-9-1), who have lost three straight and five of six. Yaroslav Askarov made 20 saves.
Kempe made an immediate impact in his return by scoring 1:23 into the game on a wrist shot from the slot on a breakaway that beat Askarov to his left stick side. He then buried a one-timer in the right circle off Erik Gustafsson’s pass to put Los Angeles up 2-0 at 16:09.
Byfield made it 3-0 on a power play at 18:38 of the first, waiting in the slot for a one-timer off Panarin’s pass. Kempe had the secondary assist as the Kings scored with the man-advantage for the third straight game.
The Sharks cut it to 3-1 on Celebrini’s sixth goal of the season at 5:07 of the second period. Celebrini beat Kuemper with a wrist shot from the high slot through traffic on a power play.
Erik Haula restored a three-goal margin for Los Angeles by making it 4-1 at 11:10 on a backhand from the slot set up by Kenny Connors’ centering pass from the left goal line along the glass. It was Connors’ first assist and point in three NHL games.
Kempe got his hat trick at 15:51 of the second period by putting in Alex Laferriere’s cross-slot pass with a one-timer from the left circle to give the Kings a 5-1 lead. Kempe’s fifth career hat trick moved him into a tie with Charlie Simmer and Jimmy Carson for ninth in Kings history.
Joel Armia made it 6-1 at 2:12 of the third period by attacking the crease and sweeping in Haula’s centering pass.
Stenberg’s shot from the left circle redirected in off Kings defenseman Joel Edmundson on a power play at 9:41 to pull within 6-2 before Byfield tipped Panarin’s shot at 14:28 for the 7-2 final.
