目的:系统分析2019新型冠状病毒肺炎（COVID-19）患者的凝血特征。方法:计算机检索PubMed、Scopus、Web of Science、EMbase、中国知网数据库，搜集报道COVID-19凝血特征相关的文献，检索时限均为2020年1月1日至5月1日。由2名研究员独立筛选文献、提取数据并评价纳入研究的偏倚风险后，采用Stata12.0软件对不同疾病分型COVID-19患者的血小板计数、D-二聚体、凝血酶原时间（PT）、活化的部分凝血活酶时间（APTT）、纤维蛋白原（FIB）进行Meta分析。结果:共纳入39个回顾性研究，共计6 994例COVID-19患者。Meta分析结果显示：（1）与重症患者相比，轻症患者的血小板计数较高［加权均值差（WMD）=20.11，95%n CI 11.53~28.69，n P<0.001］，APTT（WMD=1.30，95%n CI 0.31~2.30，n P=0.01）更长，D-二聚体（WMD=-0.41，95%n CI-0.58~-0.24，n P<0.001）、FIB（WMD=-0.58，95%n CI-0.76~-0.39，n P<0.001）较低，凝血酶原时间（PT）（WMD=-0.51，95%n CI-0.92~-0.10，n P<0.001）更短；危重患者血小板计数较低（WMD=-14.75，95%n CI-29.73~-0.23，n P=0.044），D-二聚体较高（WMD=1.06，95%n CI 0.65~1.47，n P<0.001）。（2）与存活组相比，死亡组患者血小板计数较低（WMD=-36.40，95%n CI-63.23~-9.58，n P=0.008），D-二聚体较高（WMD=6.86，95%n CI4.15~9.57，n P<0.001），PT（WMD=1.37，95%n CI0.73~2.02，n P<0.001）更长。n 结论:凝血功能紊乱在重症、危重症和死亡的COVID-19患者中较常见。血小板计数、D-二聚体和PT值与病情严重程度相关，可作为住院期间病情恶化的早期预警指标。“,”Objective:To systematically analyse the blood coagulation features of coronavirus disease 2019 (COVID-19) patients.Methods:An electronic search in PubMed, Scopus, Web of Science, EMbase, and CNKI to collect studies related to the blood coagulation features of COVID-19 patients from 1 January 2020 to 1 May 2020. Two reviewers independently screened literatures, extracted data and assessed the risk of bias of included studies. Then, the platelet count, D-dimer value, prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen of patients with different types of diseases were analyzed by using Stata12.0 software.Results:Thirty-nine retrospective studies involving 6 994 COVID-19 patients were included. The results of meta-analysis showed that:(1) compared with severe group, the platelet count (Weighted mean difference; WMD=20.11, 95%n CI 11.53 to 28.69, n P<0.001) and APTT (WMD=1.30, 95%CI 0.31 to 2.30,n P=0.01) were found to be higher while D-dimer (WMD=-0.41, 95%CI-0.58 to-0.24, n P<0.001), fibrinogen (WMD=-0.58, 95%n CI-0.76 to-0.39, n P<0.001) and PT (WMD=-0.51, 95%CI-0.92 to-0.10,n P<0.001) were lower in mild group; the platelet count (WMD=-14.75, 95%n CI-29.73 to-0.23, n P=0.044) was found to be lower while D-dimer (WMD=1.06, 95%n CI 0.65 to 1.47, n P<0.001) was found to be higher in critical ill patients. (2)Compared with the survival group, the patients in death group displayed elevated levels of D-dimer (WMD=6.86, 95%n CI 4.15 to 9.57, n P<0.001) and PT (WMD=1.37, 95%n CI 0.73 to 2.02, n P<0.001) while platelet count (WMD=-36.40, 95%n CI-63.23 to-9.58,n P=0.008) remained low.n Conclusion:Coagulation dysfunction was common in severe, critical ill and dead COVID-19 patients. Platelet count, D-dimer and PT levels were associated with the severity of the disease, and thus could be used as early warning indicators for the deterioration of the disease during hospitalization.