This study included 15 patients with gynaecological cancers (7 with cervical cancer, 6 with endometrial cancer, and 12 with ovarian cancer); 7 with benign gynaecological disorders (5 with benign ovarian tumour and 2 with uterine myoma); and 10 healthy women as a control group. Serum interleukin-1 receptor antagonist (IL-1 ra) levels in patients with gynaecological cancer were significantly higher than those in patients with benign gynaecological disorders (P = 0.04) and in healthy controls (P = 0.0009). IL-1 ra may play an important role in host immune responses in local and general environments against gynaecological cancers.