Based on the Complex Dynamic Systems theory, this qualitative case study investigated the English learning agency of five Uyghur students majoring in English at a university in Northeast China. Through the analysis of reflective journals, self-plotted graphs and semi-structured interviews, the study found that the development of Uyghur university students’ English learning agency was characterized as non-linear, personal and spatially temporally situated. The developmental trajectories were both converged and deviated and there were distinct individual differences among the five students. In addition, the development of agency was the result of the interaction between individual and external environmental factors. These findings have implications for minority students’ English teaching at universities and basic education in minority areas.