Does someone know a good tapas bar in Barcelona?

Of course ! But it depends which kind of tapas you like. For regular tapas you can go to tapa tapa in Passeig de Gracia,44, you can also go to El Somiatruites calle Regomir, 16. If you like cheese, i have tasted CheeseMe Plaça Jacint Reventós and it's very nice ! And the last but not the least, H-Original which offer typical catalan dishes and Tapas, closed to MACBA.

Another very good Tapasbar in Barcelona is Taller de Tapas which I can recommend to everyone. There are some in Barcelona, I have been in those above and the location is very nice.
C/de l'Argenteria 51 (Born district)
+ 34 93 268 85 59
www.tallerdetapas.com

I would definetly recommend the bar "Divinus", it is in Passeig de gracia. It has great tapas to a good price. And their Sangria is also excellent!

Taller de Tapas is very famous as well. In Barcelona you can find 4 of those Tapas Bars. I know the one in Carrer de l'Argenteria and it is very good.

Here you can have a look on the website of Taller de Tapas.