Objective：To investigate the application value of Doppler uterine artery imaging and pelvic ultrasound combined with morning urine gonadotropin in the preliminary diagnosis of central precocious puberty（CPP）in girls. Methods：A total of 96 precocious girls admitted to the Department of Pediatrics，Huai’an Clinical College，Xuzhou Medical University from April 2022 to May 2023 were recruited as the study objects. General data were collected，serum basic luteinizing hormone（LH），follicle stimulating hormone（FSH），and estradiol levels were examined，morning urine LH and FSH were determined，and bone age was detected. At the same time，pelvic Doppler ultrasonography was performed to evaluate the uterine artery pulse index（PI），long diameter，transverse diameter and anteroposterior diameter of uterine，uterine volume，and ovarian volume. The girls were divided into the non-CPP group and the CPP group according to the results of GnRH stimulation test. Statistical software was used to analyze and integrate relevant data. Results：①The level of the uterine artery PI in the CPP group was significantly lower than that in the non -CPP group，while uterine long diameter as well as the level of morning urine LH in the CPP group were significantly higher than those in the non-CPP group（P ＜ 0.05）. ②Correlation analysis showed that uterine artery PI was negatively correlated with morning urine LH，morning urine FSH，long diameter，transverse diameter，anteroposterior diameter of uterine，uterine volume，ovarian volume，and serum LH peak value （P ＜ 0.05），but had no significant correlation with serum FSH peak value（P ＞ 0.05）. Uterine long diameter was positively correlated with morning urine LH，morning urine FSH，uterine transverse diameter，anteroposterior diameter，uterine volume，ovarian volume，and serum LH peak value（P ＜ 0.05），but had no significant correlation with serum FSH peak value（P ＞ 0.05）. Morning urine LH level was positively correlated with morning urine FSH，uterine long diameter，transverse diameter，anteroposterior diameter，uterine volume， ovarian volume，serum LH peak and FSH peak（P ＜ 0.05）. ③The area under curve（AUC），sensitivity and specificity of ROC curve when uterine artery PI，uterine long diameter，and morning urine LH were used for diagnosing CPP in girls were 0.915，76%，90%； 0.945，95% ，88% ；0.925，91% ，84% ，respectively. When uterine artery PI，uterine long diameter，and morning urine LH were combined in the diagnosis of CPP in girls，the AUC，sensitivity and specificity were 0.974，98% and 90%，respectively，which was better than used alone. Conclusion：The combined determination of uterine artery PI，uterine long diameter and morning urine LH display the highest efficacy in the diagnosis of CPP in girls，and has the advantages of safety，non -invasive and convenient，which is suitable for clinical application.