In this study, work ethic was examined as a predictor of academic motivation and performance. A total of 440 undergraduate students completed measures of work ethic and academic motivation, and reported their cumulative grade point average. Results indicated that several dimensions of work ethic were related to academic motivation and academic performance. Differences between correlations were examined, and work ethic dimensions were more strongly related to hypothesised dimensions of motivation than other dimensions of motivation. In addition, structural equation modelling was used to examine the mediating effect of academic motivation. These findings provide additional evidence for the importance of work ethic in academic settings, as well as important construct-related validity evidence for work ethic. Implications of these study findings, limitations and future directions are discussed.