Two genomic bacterial artificial chromosome (BAC) libraries were constructed for the grass carp (Ctenopharyngodon idella), using the CopyControl pCC1BAC/EcoRI cloning vector and pCC1BAC/HindIII respectively. The former library consists of about 53000 clones arrayed in 138 384-well microtiter plates. NotI restriction analysis of 150 white clones picked randomly indicated the average insert size of BAC library is 139.7 kb and the frequency of clones without inserts is 2%. Based on the grass carp haploid genome size of 1000 Mb, this library represents approximately 7.4-fold genome coverage. Theoretically, the probability to find any unique sequence in library screening is 99.93%. The later BAC library consists of a total of 52216 clones with an average insert size of 121.5 kb and there are less than 2.8 % of empty clones. This library is estimated to contain approximately 6.3 genome equivalents of the genome of the grass carp. These are the first BAC libraries constructed from this species. High-density filters were prepared, each containing an array of 4 plates in duplicate. Those libraries can be utilized for cloning of genes and molecular markers for selection of strains with economic traits and constructing the physical genome map for whole genome sequencing and comparative genome study, witch will provide profound molecular knowledge and a technology platform to improve the genetic traits of grass carp and other farm cyprinid species.