Betis seemed to have wrapped up the game inside the first half an hour after going 3-0 up.
Benat made it 3-0 to Betis just five minutes later when he found the target from outside the Bilbao penalty area.
However, the Basque giants came back strongly in the second period, with Oscar De Marcos pulling one back just two minutes into the restart from close range after being released by Aritz Aduriz with a through ball.
Marcelo Bielsa's side scored their second goal of the match midway through the second half through Mikel San Jose header.
San Jose was on the scoresheet again in the 76th minute with yet another header, as Bilbao made it 3-3.
However, Betis had the last laugh in this exciting La Liga clash, as Alex Pozuelo and Molina scored in the final 10 minutes to round off a 5-3 win.