This study investigated the socio-economic determinants of learning achievements in primary schools in Uganda focusing on the primary six pupils. The objectives of the study were; to find out how pupils’ home and family background determine their learning achievements, to investigate the effect of pupils’ characteristics on learning, to study the effect of teacher characteristics on pupils’ learning achievement and to examine the effect of school characteristics on pupils’ learning achievements. Southern African Consortium for Monitoring Education Quality III 2007 data set was utilized in this study. The data was collected using a stratified two-stage cluster sample design. The levels of data analysis included univariate were frequency tables and descriptive statistics were used to explain background information. At Bivariate level, statistical significance of the association between the dependent variable and the independent variables were established using Pearson chi-square test with the significance level fixed at 5%. Exploratory factor analysis was used to come up with latent variables that were finally fitted in the linear regression model, with pupil performance as the dependent variable.