Abstract: Objective： Retrospective study investigating hospitalized patients using linezolid， to investigate the occurrence and related factors of linezolid-related thrombocytopenia. Methods： Using retrospective case study survey analysis， analysis of patients taking linezolid from June 2015 to December 2017 at Shengjing Hospital of China Medical University， and analysis of the incidence of patient-related thrombocytopenia in 260 patients treated with linezolid. The t-test (parameter) and the Mann-Whitney U test (non-parameter) were used， and the χ2 test was used to analyze the difference between the groups. Conditional logistic regression was used to analyze the influencing factors of adverse reactions/events and their standard regression coefficients (degree of influence).α=0.05. Results： In this study， 67 patients developed thrombocytopenia after the use of linezolid， with an incidence of thrombocytopenia occurrence rate is 25.77% .Univariate analysis showed that the incidence of blood was 35.40% (χ2=9.80) in the age group over 65 years old. The incidence rate of 3 or more combined drug groups was 34.07% (χ2=11.02%). Analysis showed that laboratory indicators， platelet basis values， days of medication， albumin， creatinine， urea， uric acid and thrombocytopenia were associated (P<0.05). Multivariate logistic regression analysis (backward：wald) showed that： platelet basic value， medication days， bile duct. The area under the predictive curve of ROC diagnostic curve was 0.738， sensitivity was 68.71%， specificity was 71.50% and Youden index was 0.40. Conclusion： The incidence of thrombocytopenia after linezolid is high， univariate analysis shows that we should focus on the elderly (≥65 years old)， combined therapy (≥3)， and basic platelet value. Multivariate analysis showed that platelet basal value， medication days， bilirubin and creatinine were closely related to the occurrence of thrombocytopenia.