In the past few decades a growing research interest in internal and external factors that contribute to a student's motivation to learn has yielded numerous models and theories. Despite their similarities, these theories have tended to be developed and tested independently of each other, although some connections have been made between them. The aim of this study is to investigate connections between key aspects of two theoretical approaches: the attributional theory (Weiner, 1985, 1992) and self-determination theory (Deci and Ryan, 2000). Specifically, this study investigates the relationship between four types of regulatory styles of learning and students' causal attributions of their attained academic achievement. The participants were 127 elementary school students (Median age = 13.71) in Croatia. First, students assessed their final mid-term grades either as success or failure (subjective appraisal of successfulness), after which the Academic Self-Regulation Questionnaire of Ryan and Connell (1989) and the Causal Attribution Scale of Soric (1998) were applied. The results showed that intrinsically motivated successful students, who feel autonomous and self-determined rather than controlled by others, attributed their success to more internal and controllable causes. But associations between other regulatory styles and causal dimensions still remain unclear, especially in the case of failure situations. (Contains 4 tables.)