We developed a numerical method based on the Level Set method, which can simulate biological cell behavior in micro channels. The isotropic compliant wall model is used to model the cell membrane and the surface force is calculated from the local displacement of membrane computed by using the Level Set function. The biological cell model behavior is investigated in a channel with sudden expansion and contraction. The shape of the cell model is found to be elongated in the contracted region and semicircle in the expanded region. The collision between two cell models in a T-junction is also investigated. When the cell models touch with each other, their boundaries overlap. A repulsion model is proposed to avoid this overlap.