Michael Young drove in two runs and scored twice for the Rangers, who have won seven of their last eight games and lead the Angels by five games.
The Rangers outhit the Athletics 14-3.
Derek Holland (15-5) allowed one run on two hits and struck out seven to win his fourth consecutive decision.
Rich Harden (4-4) was tagged with the loss. Harden lasted only three innings and allowed six runs -- five earned -- on seven hits.
Beltre's homer staked the Rangers to a 3-0 lead in the first inning. Texas widened the gap to 5-0 after three innings.