Abstract: The technology of expressed sequence tag ( EST) was broadly applied in analysis of gene function and expression pattern. Based on the construction technology of non-normalized cDNA library, the cDNA libraries of grass carpps intestinal cDNA Library was constructed. This library reaches 2. 3 *105in capacity; the percenyage of recombination is as high as 95%. PCR results showed that the average size of inserts was larger than 1000 bp. And a total of 1571 successful sequencing reactions yielded 1411 which expressed sequence tags ( ESTs) longer than 100 bp. In addition, 939 non-repetitive sequences were formed including 188 contigs and 751 singletons from these ESTs after initial assembly. BasicLocal Alignment Search Tool (BLAST) analysis showed that nearly 44.5% of the sequences were assigned putative functions because they showed similarity to known genes (E-valueCtenopharyngodon idellus.