Background: The prevalence of gestational diabetes mellitus (GDM) has been increasing globally, which has led to substantial implications for long-term maternal health including diabetes. The present study aimed to explore the rate of postpartum glucose screening (PGS) of women with GDM based on WeChat management and explore factors affecting the rate of PGS and impaired glucose regulation (IGR). Methods: In this prospective trial, GDM patients were enrolled in our WeChat platform groups. Demographic and medical data were collected at the baseline surveys and follow-up visits. GDM patients were managed throughout their pregnancies via the WeChat platform. We sent messages, involving multidisciplinary care, medical nutritional therapy, and glucose monitoring every three days in the chat groups, and reminded them to go to the hospital to complete PGS. Questionnaires about PGS via the WeChat platform were sent to those women who had delivered within 4 to 12 weeks postpartum. Answers to the questionnaires [understanding the necessity of postpartum oral glucose tolerance testing (OGTT) screening, and the results of 42-day postpartum OGTT screening, as well as the reasons for failing to finish postpartum screening, and the ways to get nutrition knowledge for GDM patients] were collected. Results: From 1 January 2016 to 31 August 2019, 490 participants were included in our WeChat groups, 375 of whom completed questionnaires. Among the 375 participants, 277 (73.9%) had completed post-partum 75 g OGTT, 202 (72.9%) had normal glucose levels, and 75 (27.1%) had impaired glucose regulation (IGR). Univariable logistic analysis and stepwise regression analysis demonstrated that a previous history of GDM and cesarean delivery were the two variables influencing PGS (odds ratio (OR): 0.44, 95% confidence interval (95% CI): 0.20–0.94; OR: 1.88, 95% CI: 1.04–3.39, respectively). Insulin treatment during pregnancy and cesarean delivery were found to have a significant association with postpartum IGR (OR: 3.74, 95% CI: 1.97–7.08; OR: 1.83, 95% CI: 1.02–3.28, respectively). Conclusions: The WeChat messaging platform may be a useful tool to promote postpartum OGTT screening in women with GDM. Women who failed to return for PGS were more likely to have prior GDM than those who returned for PGS. Women who had postpartum IGR were more likely to use insulin treatment during pregnancy and more likely to deliver by cesarean delivery compared to those who had normal postpartum glucose results. Clinical Trial Registration: The present study was registered at ClinicalTrials.gov Protocol Registration and Results System https://classic.clinicaltrials.gov/ (No. NCT02893072).