Gasol sat out the first 11 games of the season while nursing a strained right hamstring. He was 9-of-15 from the floor in his season debut.
Kobe Bryant finished with 21 points, nine rebounds and eight assists for the Lakers, who have won two straight games after dropping two straight.
Bryant passed Kareem Abdul-Jabbar to take over second place as the Lakers' all-time scoring leader. With has 24,182 points, he trails only Jerry West (25,192).
Derrick Rose had 20 points and six assists, John Salmons scored 18 and Brad Miller had 15 for the Bulls, who lost for the first time in three games. Joakim Noah had 12 points, 15 rebounds and four steals for Chicago.