To find diapause-related genes, we were performed by differential hybridization with three types of [${alpha}-^{32}P$]dCTP-labeled total cDNA probes synthesized from diapause-prepared, diapause-maintained and diapause-activated stage of Bombus ignitus queen. Nine individual cDNA clones were found to be differentially expressed in diapause-maintained and diapause-activated stage. Among these clones, BIDC9(BIDC ; Bombus ignitus differentially expressed clone) was analyzed through full-length sequencing and expression pattern analysis. This clone was specifically expressed in the thorax organ. The effect of Juvenile hormone analog(JHA) and $CO_2$ treatment was examined. JHA treatment induced the expression of BIDC9 cDNA clone abruptly after 4 day of treatment. $CO_2$ treatment induced also the clone after 2 day of treatment. BIDC9 cDNA was identified as Bombus ignitus diapause gene contained an open reading frame of 1376 bp encoding 255 amino acids.