The authors explored the effects of general mental ability and motivation (operationalized as conscientiousness) on performance in an online distance education course. The results supported the hypotheses that both higher levels of motivation and higher general mental ability are positively associated with academic performance in a distance learning environment, while low levels of either motivation or general mental ability were associated with lower levels of performance. The results also support the presence of a significant interaction effect between motivation and general mental ability in terms of their relation to performance. High levels of either motivation or general mental ability alone with low levels of the other factor did not produce high levels of performance, demonstrating the importance of simultaneously considering both factors. Theoretical and practical implications of the results are discussed.