The aim of this study was to examine the relationship between need for cognition, achievement goals and behavioral, cognitive and emotional dimensions of engagement in learning mathematics within the hierarchical model of achievement motivation framework (Elliot i Church, 1997). The participants were 543 first to fourth grade students from general, language and mathematical gymnasiums. Instruments used in this study were: Need for cognition scale, Achievement goal scale and Engagement in learning mathematics scale. Results suggest that achievement goals have distinct patterns of relationships with dimensions of engagement. Mastery-approach goal showed the most adaptive pattern, while performance-avoidance showed the least adaptive pattern of relationships with engagement. Need for cognition was positively correlated to all three dimensions of engagement. Also, it was positively correlated to mastery-approach and performance-approach goals, negatively correlated to performance-avoidance goal and unrelated to mastery-avoidance goal. The multiple mediational analyses showed that achievement goals have a significant mediational role in positive relationship between need for cognition and all three dimensions of engagement. Higher mastery-approach goal mediated positive relationship between need for cognition and all three dimensions of engagement, while lower performance-avoidance goal mediated only positive relationship between need for cognition and emotional engagement.