Which one is earth like planet in Gliese 581?

None of them are particularly Earth-like. Gliese 581 d and Gleise 581 g are the two planets in the system considered most likely to have terrestrial-type life, but neither is a particularly good candidate. As seen from a distance, Venus is actually more like the Earth than any of the known planets in the Gliese 581 system; and as far as we can tell, Venus is extremely inhospitable.

Observations suggest that the star has at least six planets: Gliese 581 e, b, c, g, d and f. Significantly, planet g is thought to be close to the middle of the star's habitable zone.

http://en.wikipedia.org/wiki/Gliese_581

With a mass 3.1 to 4.3 times Earth's, Gliese 581 g is considered a super-Earth, and is the planet closest in size to Earth known in a habitable zone. This makes it the most Earth-like Goldilocks planet found outside the Solar System and the exoplanet with the greatest recognized potential for harboring life.

http://en.wikipedia.org/wiki/Gliese_581_g