This paper developed a measure of job motivation toward business firm. Two processes were conducted to validate this measure. For this processes, 313 employees completed the questionnaires and SPSS and Amos 4 were employed. The first process confirmed the factor structure of the scale and revealed a satisfactory level of internal consistency and the construct validity of the scale: A measure of motivation consists of five subscales that measure intrinsic, identified, introjected, extrinsic, and amotivation. The second process revealed some relations among the subscales and between the subscales and other relevant variables. Some positive relationships among four types of motivation except amotivation have been found. The relation between job autonomy and five types of motivation was partially revealed. Pay for performance was related to extrinsic and intrinsic motivations. Job involvement was related to intrinsic motivation while work effort was related to identified and introjected motivations. Intention to leave was positively related to amotivation. Some implications of these results are discussed.