The purposes of this study were to investigate the predictors on Physics learning achievement. Subjects were 243 Mathayom Suksa Four Students in the 1979 academic year from Secondary Schools in the Bangkok Metropolis. Instruments administered to all subjects were: six test on Abilities in Computation, Spatial Relation, Graph Interpretation, Attitude toward Science, Attitude toward Physics and Physics Learning Achievement. The data obtained were analyzed by means of forward stepwise multiple regression analysis. The results indicated that at the 0.01 level there were significant positive correlations between the Physics learning. achievement and each of the five traits; ablilties in computation, spatial relation, graph interpretation, attitude toward science, attitude toward physics. It was also found that the abilities in computation was the best predictor. The effective prediction equation for estimating the Physics learning achievement was The Physics learning achievement = 0.4847 (abilities in computation) +0.4115 (graph interpretation) +0.1965 (attitude toward science) The multiple correlation of the three traits with the criteria is 0.78136