The purpose of this study is to determine undergraduate students' attitudes and mathematics beliefs and examine the effects of these variables on mathematics achievement. The study was designed according to the relational survey model. Total of 334 undergraduate students educated in the primary school teaching department formed the study group of research. In the study, as data collection tools, "Attitude towards Mathematics Scale" and "Mathematics Belief Scale" were applied respectively. In the process of data analysis; descriptive statistics, Pearson Moment Correlation and multiple regression analysis were applied. As a result, it was found out that the attitudes and beliefs of primary school undergraduate students towards mathematics were moderate. On the other hand, it was concluded that students' attitudes and beliefs towards mathematics also predicted their mathematics achievement scores. Besides, it can be suggested to examine the variables such as anxiety, self-efficacy and professional attitude among the affective factors affecting mathematics achievement.