Abstract: The cDNA libraries were constructed from the kidney and normal unfertilized eggs of the silkworm, Bombyx mori and sequenced at random in order to study the maternal genetic information contained in the silkworm's eggs. We had successfully sequenced 391 ESTs (expressed sequence tag) and obtained 374 unigenes after assembling. Bioinformatics analysis indicated 172 unigenes had significant similarity with the known genes recorded in GenBank and silkbase. Except three known maternal genes, the rest were mainly related to replication, metabolism，signal transduction, transcription factor, protein structure and embryo development. These results will provide source for further study on the development regulation of early embryo of the silkworm.

Key words: Silkworm, expressed sequence tag, unfertilized eggs, embryo development, maternal gene