Background: Occupational injury is an unintentional physical damage or injury resulting from an occupational accident. In developing countries, an occupational injury is one of a major problem in the field of public health. This study aims to assess prevalence and factors associated with occupational injury among level one general contractor firm building construction workers in Bole Sub –city, Addis Ababa.rnMethods: Institutional-based cross-sectional study was conducted in 12 licensed level one General contractor firms in Bole sub-city from March 01-17, 2017. Stratified sampling technique was used which includes 804 study subjects. Data were collected via face to face interview; Data entry and analysis were used Epi data version 3.1 and SPSS version 21 software package respectively. Descriptive statistics mean, frequency and percent were performed for most variables, bivariate analysis were preformed, Variables with 95% confidence intervals and P value at