Barca are eyeing Gunners captain Pierre-Emerick Aubameyang and during talks, reports Mundo Deportivo, the Londoners have asked about Dembele.
The Catalans are prepared to sell the France attacker this summer - and at a knockdown price of €40m.
Arsenal are interested and Barca are keen on including him in an offer for Aubameyang.
However, Arsenal aren't alone, with Juventus asking about Dembele in recent days during talks over Miralem Pjanic's departure for Barca. The Bosnia midfielder has already agreed personal terms with the Blaugrana.