The relationship between university students' personality traits, the perception of their academic learning- environment, and the students' interest and motivation is investigated. As a theoretical framework the self- determination theory (SDT) (Deci & Ryan, 1985, 2002) and the theory of interest (Renninger, Hidi & Krapp, 1992) are applied. According to SDT it is proposed that perceived support of basic psychological needs (support of autonomy, support of competence, and social relatedness) as well as aspects of a powerful learning environment (e.g. teachers' interest, relevance of contents and quality of instruction) are associated with intrinsic motivation, self-determined forms of extrinsic motivation and with study interest. Specific "Big Five" profiles should be associated with interest and motivation in different subjects. Of particular interest was the cross-cultural testing of the theoretical assumptions of the SDT and the theory of interest. The data of a cross-disciplinary sample of undergraduate students of the University of Cape Town, South Africa (N=350) were investigated. The results show that most of the students are motivated on an intrinsic and identified level and they are provided with high individual study interest. Further results of a cluster analysis demonstrate that 34% of the students are regulating their learning processes on an introjected, identified and intrinsic level at the same time; only 28% are more externally regulated. Study interest, intrinsic motivation and self-determined forms of extrinsic motivation are significantly associated with perceived support of autonomy and competence as well as with the relevance of the contents, the quality of instruction, and with the perceived transparency of the requirements. However, in comparison with other samples, the correlations are slightly lower. In a stepwise multiple regression analysis (dependent variable "study interest") significant predictors are relevance of the contents and over-load (-) as well as the personality variables conscientiousness and openness (R2=.185***). For the dependent variable "intrinsic motivation" the predictors are support of competence, quality of instruction, over-load (-), and conscientiousness (R2=.200***). Conscientiousness is obviously an important pre-condition for intrinsic learning motivation and for study interest (as a personal disposition). Only these mentioned environmental variables of the theoretical model are relevant. Further research should focus on different aspects of the personality and the higher educational environment as predictors for motivation and study interest. The necessity of ecological experiments and longitudinal studies is obvious. With regard to the South African situation we shell look for further socio-political and cultural aspects associated with learning motivation and study interest (see McInerney & Etten van, 2001). Further investigation regarding the assumptions of the SDT in different (non western) cultural systems in needed. This study seeks to make both a theoretical and practical contribution. References: Deci, E.L. & Ryan, R.M. (1985). Intrinsic motivation and self-determination in human behavior. New York: Plenum Press. Deci, E. L. & Ryan, R. M. (2002). Overview of self- determination theory: An organismic dialectical perspective. In E. L. Deci & R. M. Ryan (Eds.), Handbook of self-determination research (p. 3-33). Rochester: University of Rochester Press. McInerney, D. M. & Etten van, S. (2001, eds). Research on sociocultural influences on motivation and learning (vol. 1). Greenwich: Age Publishing. Müller, F.H. & Louw, J. (submitted). Students' perception of the university learning-environment and its effects on motivation and interest. Empirical data from the University of Cape Town, South Africa. South African Journal of Higher Education. Renninger, K. A., Hidi, S. & Krapp, A. (Eds.). (1992). The role of interest in learning and development. Hillsdale, N.J.: Erlbaum.