The Gunners were already shorn of Mesut Ozil (knee), and Alexis Sanchez was omitted from the matchday squad as he reportedly nears an exit to either Manchester United or Manchester City.
The goal was Bellerin's second goal in consecutive EPL games for Arsenal.
That proved to be the final chance of the half as Arsenal shot-stopper Petr Cech endured a quiet opening 45 minutes.
Alexandre Lacazette, a player who has been low on confidence of late started up top - and with Sanchez departing the Frenchman now has an even bigger onus on him to become Arsenal's main goal scorer, something he couldn't manage on the day.
The Cherries nearly made the breakthrough in the 40th minute through Ryan Fraser after some great work by Jordon Ibe saw the ball fall to the Scot, but Calum Chambers came flying in to make the block.
Arsenal shocked by struggling Bournemouth
Bournemouth restored parity on 70 minutes as Callum Wilson turned home Ryan Fraser's cross to draw the hosts level, 1-1. "It doesn't matter who played, we respect all their players".
With 20 minutes remaining Bournemouth found a deserved equaliser. Bournemouth, meanwhile, climb to 13th but remain just four points above the bottom three.
INCIDENTS: Premier League fixture between Bournemouth and Arsenal at the Vitality Stadium.
- The Cherries have won their first ever game against Arsenal in all competitions (D1 L5).
"Alexis would have played, but it's a hard period for him".
Ibe's goal ended his duck 18 months after joining from Liverpool, and Howe was delighted for the winger.More news: Brown's final California budget stashes billions in reserve
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