We applied high throughput sequencing technology to identify microRNA genes in bighead carp and silver carp. We identified 167 conserved miRNAs in bighead carp and 166 in silver carp. By two computational stragegies, we obtained 39 novel miRNAs in bighead carp and 54 in silver carp, for which, no homologs were found in other species. Several miRNA* sequences were found in our dataset as well, some particular ones might have gene regulation function. Gain and loss of family members were observed in several miRNA families, which partially reflected the fate of miRNA gene duplicates. Total RNA of juvenile bighead carp and silver carp were sequenced on one Solexa lane, respectively.