Background Tardive Dyskinesia is described as a movement disorder that can be caused by the prolonged use of antipsychotics. It is a permanent condition that affects quality of life. However, studies on TD among psychiatric patients in Ethiopia are limited. The objective of this study was to determine the prevalence and associated factors of Tardive dyskinesia among psychiatric patients on first-generation antipsychotics at Jimma University specialized hospital (JUSH) psychiatric clinic, Jimma, South west Ethiopia.Method Hospital based cross-sectional study was conducted using Abnormal Involuntary Movement Scale (AIMS) and Schooler and Kane research criteria to identify cases of first-generation antipsychotic-induced TD among 151 psychiatric outpatients on first-generation antipsychotics at Jimma University Specialized Hospital psychiatric clinic. Simple random sampling method was employed to select subjects from a total of 912 patients on follow-up and logistic regression analysis was employed to identify associated factorsResult In our study the prevalence of first-generation antipsychotic induced TD was 14.6% (95%CI: 10.76%, 18.4%). In the final model multivariate logistic regression analysis revealed that age (AOR 4.5, 95%CI: 9.7, 20.4), current smoking cigarettes (AOR 1.4, 95%CI: 2.6, 7.8) and chlorpromazine equivalent dose (AOR 6.5, 95%CI: 2.6, 26.8) had statistically significant association with first-generation antipsychotic induced TD.Conclusions Considerable number of psychiatric patients were suffered from first-generation antipsychotic induced TD. Age and current smoking cigarettes and chlorpromazine equivalent dose had significant association with first-generation antipsychotic induced TD. Therefore, stakeholders should consider and appropriately address these statistically identified associated factors in order to reduce antipsychotic induced TD.