Objective: Randomized controlled trials (RCTs) are usually the basis of evidence-based medicine and provide important information for pediatric clinical practice, but whether the results of RCTs can be correctly translated into clinical practice depends on the quality of the literature reported. In this study, we evaluated the general characteristics and quality of pediatric RCTs published in mainland China over the decades 1999-2018.Methods: We individually searched all 20 available pediatric journals published between January 1, 1999, and December 30, 2018 and selected RCTs with participants less than 18 years. Each review author extracted details data from each of the selected RCTs including general characteristics, ethical characteristics, trial characteristics. Using Cochrane Collaboration methods for risk assessment.Results: Totally, 4093 RCTs were included for analysis. The average annual growth rate of published pediatric RCTs was 35.22% (p = 0.000), a notable increase occurred in 2017, and most of the studies were carried out in east China (32%). Only 1.98% of RCTs conducted in multiple-center, and 13.73% of the RCTs reported funding resources, 15.34% of the RCTs stated that it was approved by the ethics committee and 34.99% of the authors stated that the patients signed the informed consent. Comparing RCTs published in 2014-2018 with RCTs published in 1999-2003, we found the quality of RCTs has improved in random sequence generation, blinding participants and personnel, and incomplete outcome data. RCTs stated the approval of the ethics committee and the signing of the informed consent form, conducted in teaching hospitals, with multiple-centers, funding were of better quality in all the analyzed items.Conclusions: The number of pediatric RCTs has increased significantly over time in mainland China, and the quality have improved over the decades 1999-2018, but quality of the RCTs initiated by investigators published in mainland China still need to be improved, special attention should be paid to allocation concealment, blinding outcome assessment and selective outcome reporting.