The problem of this study was to investigate the relationship of the variables of impulse control, adaptive behaviors, responsible behaviors, intelligence, and duration of institutionalization to job performance of the mentally retarded student at the Denton State School, Denton, Texas. The purposes of this study were 1. to ascertain the correlation of the variables of adaptive behaviors, responsible behaviors, impulse control, duration of institutionalization and intelligence quotient to job performance of the mentally retarded student at the Denton State School; 2. to determine which factor or combination of factors would be most useful for predicting job performance effectiveness of the mentally retarded student. It was concluded that of those variables included in this study, intelligence quotient was the best single predictor of job performance. The combination which was found to be the best predictor of job performance was impulse control and intelligence quotient. The variables included in this study (adaptive behaviors, impulse control, responsible behaviors, intelligence quotient, and duration of institutionalization), taken either singly or in combination, do not correlate highly enough with job performance to be of much value for predicting job performance.