The utility of placental growth factor (PlGF) and its receptor VEGFR-1 (Flt-1) as biomarkers for cervical cancer has not been clarified yet. To address this issue, we investigated the levels of soluble PlGF (sPlGF) and soluble Flt-1 (sFlt-1) in the serum from patients with early cervical cancer, cervical intraepithelial neoplasia (CIN) and controls in this study. sPlGF and sFlt-1 were detected in 44 preoperative patients with cervical cancer, 18 cases with CIN, and 20 controls by ELISA. It was found that both sPlGF and sFlt-1 were significantly increased in the cervical cancer group as compared with those in CIN and control groups. sPlGF presented a high diagnostic ability of cervical cancer, with a sensitivity of 61.36% and a specificity of 89.47%; and sFlt-1 with a sensitivity of 50.00% and a specificity of 92.11%. Importantly, the combined use of sPlGF and sFlt-1 could increase the diagnostic rate of cervical cancer, with a sensitivity of 70.45% and a specificity of 92.11%. These results indicated that both sPlGF and sFlt-1 in circulation can serve as possible valuable diagnostic biomarkers for cervical cancer, and the combined use of them can be more valuable to diagnose the patients with early cervical cancer.