Simulation of pedestrian evacuation flow with affected visual field is carried out on the basis of cellular automata. The room to be evacuated is divided into exit visible area, wall visible area and blind area by pedestrian sight radius, and two basic dynamic parameters in the dynamic parameters model are used to simulate the varied movement characteristics of pedestrian in different evacuation areas, including normal evacuation movement, movement along the wall and movement in fixed direction. The effect of pedestrian sight radius on evacuation time is studied with evacuation signs on the wall and pedestrian stochastically moving to find the wall in fixed directions and then moving along the wall. It is observed that the evacuation time depends not only on the pedestrian sight radius but also on the length and utilization rate of exit.