ObjectiveTo systematically review the efficacy and safety of JAK inhibitor in the treatment of axial spondyloarthritis (axSpA). MethodsThe PubMed, Cochrane Library, Embase, CNKI, WanFang Data, and VIP databases were electronically searched to collect randomized controlled trials (RCTs) on the efficacy and safety of JAK inhibitors in patients with axSpA from inception to December, 2023. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies Meta-analysis was then performed using RevMan 5.3 software. ResultsA total of 7 RCTs involving 1 602 patients were included, including 852 patients in the experimental group and 750 patients in the placebo group. The results of meta-analysis showed that in terms of clinical efficacy, ASAS20 (RR=1.67, 95%CI 1.50 to 1.86, P<0.01), ASAS40 (RR=2.30, 95%CI 1.93 to 2.73, P<0.01), ΔBASFI (MD=−1.04, 95%CI −1.21 to −0.87, P<0.01), and ΔBASMI (MD=−0.30, 95%CI −0.41 to −0.19, P<0.01) of JAK inhibitors in the treatment of axSpA patients were significantly higher than those in the placebo group. In terms of safety, adverse event (RR=1.09, 95%CI 0.97 to 1.21, P=0.14) and major adverse events, such as diarrhea (RR=1.18, 95%CI 0.55 to 2.51, P=0.67), nasopharyngitis (RR=0.98, 95%CI 0.55 to 1.75, P=0.96), liver enzyme abnormalities (RR=1.83, 95%CI 0.84 to 3.99, P=0.13), and headache (RR=1.94, 95%CI 0.77 to 4.87, P=0.16) were statistically insignificant. ConclusionCurrent evidence shows that JAK inhibitors can improve the clinical efficacy in the axSpA patients, and the safety is high. Due to the limited quality and quantity of the included studies, more high quality studies are needed to verify the above conclusion.