Systematic cross-validations were used to explore the validity generalizability and transferability of the Multiple Aptitude Tests on predicting the scores of the Basic Scholastic Ability Tests. 1304 junior high school students in Taiwan were divided into four samples. The resulsts showed eight aptitudes could explained 45% to 49% of variances of the Basic Scholastic Ability scores. The validity generalizability and transferability were good. The major contributions of predictions came from spelling, numerical reasoning, verbal reasoning, language usage, clerical speed and accuracy.