A three-dimensional, two-phase, multiple-component, unsteady model for the anode side of passive direct methanol fuel cells is presented in this work. The model is formed by a drift-flux model and can capture in-plane distributions of species along different directions in the cell. After grid independency test, this model is used to investigate numerically transport behaviors in the anode of liquid feed direct methanol fuel cells. The results illustrate the feasibility of the passively delivering methanol to the electrochemical reaction site, and characterize the relevant transport phenomena. Moreover, the evolution of species concentration, velocities along different directions in the cell and the mass transfer limitation were also presented. The three-dimensional model is valuable for understanding and predicting mass transfer in passive direct methanol fuel cells.