To compare the diagnostic efficiency of a fluorescence colposcope with TMTP1-PEG4-ICG dye versus a conventional colposcope with acetic acid and Lugol's iodine in identifying cervical precancerous lesions.In all, 218 women with abnormal cervical cancer screening results including cytology and/or human papillomavirus (HPV) test were involved in the randomized controlled trial. Patients in the fluorescence colposcope group had TMTP1-PEG4-ICG dye applied to the cervix uteri before colposcopy. Patients in the conventional colposcope group were routinely administered acetic acid and Lugol's iodine to stain the cervix uteri. Two to four cervical sites per patient were taken out for biopsy. The diagnostic efficiency of fluorescence colposcopy and conventional colposcopy was calculated on a per-patient and per-site basis. χ2 test or Fisher exact test was used.A total of 194 patients and the corresponding 662 cervical sites were included in the final analysis. There was no statistically significant difference in the diagnostic efficiency between the two groups both on a per-patient and a per-site basis, including accuracy, sensitivity, specificity, positive predictive value, and negative predictive value.The fluorescence colposcope with TMTP1-PEG4-ICG dye was comparable to the conventional colposcope in identifying cervical precancerous lesions.© 2023 The Authors. International Journal of Gynecology & Obstetrics published by John Wiley & Sons Ltd on behalf of International Federation of Gynecology and Obstetrics.