It is well known that LDPC decoding is computationally demanding and one of the hardest signal operations to parallelize. Beyond data dependencies that restrict the decoding of a single word, it requires a large number of memory accesses. In this paper we propose parallel algorithms for performing in GPUs the most demanding case of irregular and long length LDPC codes adopted in the Digital Video Broadcasting – Satellite 2 (DVB-S2) standard used in data communications. By performing simultaneous multicodeword decoding and adopting special data structures, experimental results show that throughputs superior to 90 Mbps can be achieved when LDPC decoders for the DVB-S2 are implemented in the current GPUs.