Intrinsic motivation is deemed significant in one’s activity because it positively affects one’s behavior and performance. This descriptive-correlational research employs survey instruments with 37 statements, scoring 1 (totally untrue) to 7 (very true). It aimed to know the intrinsic motivation level in learning mathematics and its correlation with economics-mathematics subject learning achievement. The study participants were 93 undergraduate students majoring in accounting and management. The result of the study showed that students had moderate intrinsic motivation in terms of felt pressure and tension; high intrinsic motivation in terms of interest or enjoyment; perceived competence; effort or importance; and perceived choice; and very high intrinsic motivation in terms of value or usefulness. Furthermore, the study revealed that the achievement level is high. However, there is no significant correlation between students’ intrinsic motivation and their achievement in economics and mathematics. The result implies that students’ intrinsic motivation does not necessarily correlate with academic achievement. This study recommends future research consider other factors that could be associated with students’ achievement, such as instructional strategies and methods, students’ extrinsic motivation, curriculum, or the learning environment