We have created a Bovine Genome Database, an integrated genomic resource for Bos taurus, by merging bovine data from various databases and our own data. We produced 55,213 Korean cattle (Hanwoo) ESTs from cDNA libraries from three tissues. We concentrated on genomic information based on Hanwoo transcripts and provided user-friendly search interfaces within the Bovine Genome Database. The genome browser supported alignment results for the various types of data: Hanwoo EST, consensus sequence, human gene, and predicted bovine genes. The database also provides transcript data information, gene annotation, genomic location, sequence and tissue distribution. Users can also explore bovine disease genes based on comparative mapping of homologous genes and can conduct searches centered on genes within user-selected quantitative trait loci (QTL) regions. The Bovine Genome Database can be accessed at http://bgd.nabc.go.kr.