In the Spurs' season opener on October 17, Aldridge recorded 21 points and 19 rebounds in a 112–108 win over the Minnesota Timberwolves. On October 22, he had 37 points and 10 rebounds in a 143–142 overtime win over the Los Angeles Lakers. On December 29, he scored 38 points in a 122–111 win over the Los Angeles Clippers. On January 10, 2019, he scored a career-high 56 points in a 154–147 double-overtime victory over the Oklahoma City Thunder. On January 31, 2019, he was named a Western Conference All-Star reserve. On February 2, he had 25 points and 14 rebounds in a 113–108 win over the New Orleans Pelicans, thus reaching 18,000 points and becoming the only player in the league with 18,000 points and 7,500 rebounds since 2006 (the year he was drafted). On March 24, he had 48 points and 13 rebounds in a 115–98 win over the Boston Celtics.