Background: There are few randomised controlled trials (RCTs) in paediatric surgery, and their risk of bias is unknown. There is also little known about the methodological or reporting quality of systematic reviews (with or without meta-analyses) in paediatric surgery. Therefore, we conducted a cross-sectional meta-research study to determine the risk of bias and reporting quality of RCTs and systematic reviews and meta-analyses in paediatric surgery, and the associations between these outcomes and study characteristics. Methods: We searched MEDLINE, Embase, Cochrane Library, JBI EBP Database, Centre for Reviews and Dissemination and Web of Science for all RCTs and systematic reviews in paediatric surgery published in 2021. We also searched the 2021 indexes of high-impact paediatric surgery journals. We assessed the risk of bias and reporting quality of RCTs using the RoB 2 and CONSORT tools respectively. We assessed the same parameters for systematic reviews and meta-analyses using the ROBIS and PRISMA tools.  Findings: We found 82 RCTs and 289 systematic reviews/meta-analyses published in 2021. More than half (n=46, 56%) of RCTs and almost all (n=278, 96%) systematic reviews and meta-analyses were at high risk of bias. Only one (1%) RCT and four (1%) systematic reviews and meta-analyses were adequately reported. Less than half (n=37, 45%) of RCTs and just over a quarter (n=77, 27%) of systematic reviews and meta-analyses had a registered protocol. Surprisingly, we found that more than half of systematic reviews and meta-analyse (n=162, 56.1%), had no risk of bias assessment.  Conclusions: Recently published RCTs and systematic reviews in paediatric surgery are at high risk of bias and have poor reporting quality. Journals, universities, and research institutions should train authors to conduct and report higher quality studies and develop strategies to reduce risk of bias. However, research with high bias and low reporting does not necessarily lack value.