Since insulin-like growth factors (IGFs) are known to play critical roles in the development of cancers, we examined the expression of the mRNA and protein of IGF-binding protein (IGFBP) and cognate receptors to assess their possible involvement in gynecological malignancy. The specimens were obtained from 46 endometrial, 32 cervical, and 20 ovarian cancers, and 28 normal endometrium. In endometrial cancers, IGFBP-1, -2, -3 and IGF-1 receptor (IGF-1R) mRNAs were detected in 8.7, 89.1, 95.6, and 91.3% of tumors, respectively, and the corresponding proteins in 54.3, 54.3, 95.6, and 91.3% of tumors, respectively. Clinical staging was significantly related to the expression of IGFBP-1 and -2 proteins. In ovarian cancers, their mRNAs were detected in 10.0, 90.0, 95.0, and 100.0%, and proteins in 15.9, 50.0, 90.0, and 80.0%. In cervical cancers, their mRNAs were detected in 6.3, 90.6, 96.8, and 87.5%, and proteins in 44.4, 18.8, 84.4, and 87.5%. IGF-1R was highly expressed in all specimens. The abnormally balanced co-expression of IGFBPs and high levels of IGF-R in gynecological cancers suggest that IGF signals might be involved in the growth of these tumors.