Background: Legal substances use is prevalent in Ethiopia. Substance use can have several health problems that are potentially harmful in educational performance, social issues, psychological and physical well being. This study aimed to know the prevalence of lifetime and last month’s substance use and its associated factors among technical and vocational education and training College students in Ataye town. Methods: An institution-based cross-sectional study conducted from 1 March to last May 2019. Participants selected by using a simple random sampling technique. Data collected by using a structured and pretested self-administered questionnaire. Data collected by five trained diploma nurses with close supervision. Odds ratio with their 95% confidence interval, and p-value less than 0.05 used to declare the statistical significance of associated factors. Results: Four hundred eighty-three individuals participated in the study, which was a response rate of 94%. The prevalence of lifetime legal substance use was 32.5% (95% CI: 28.2, 36.5). The prevalence of last month's legal substances use was 21.9% (95% CI= 18.2, 25.5). Among lifetime legal substance users, the majority (25.5%) chewed khat. The others, (19.5%) drunk alcohol, and, 15.3% smoked cigarettes in a lifetime. Lifetime cannabis and cocaine users were 2.5%, and 7.2% respectively. Among last month's legal substance users, (21.9%) chewed khat followed by alcohol drinking (16.6%), and cigarette smoking (15.3%). In the last month, 1.2% and 3.3% of students used cannabis and cocaine respectively. Multivariate logistic regression showed that being male, having a divorced family, living greater than twenty years in the town, having substance user family members, having intimate friend substance users, and easy availability of substances were independent predictors of lifetime legal substances use. Conclusions: The prevalence of last month and lifetime legal substance use at Ataye Technical and Vocational Education and Training ( TVET ) college students were analogous with most studies done in Ethiopia. It is advisable if furthers emphasis is given for TVET students with the predictor variables.