An indoor experiment was made to analyze lateral friction of pile in expansive soil under the condition of different loads and time. The fitting curves of the obtained results of the relationship between lateral friction and loads or times showed as follows: given the same time，the lateral friction along the pile increase almost linearly with the loads，the nearer the parts from the pile top，the faster the lateral friction development of the parts，while for the parts nearer the pile end，their lateral friction increase less fast compared with the parts nearer the pile top，given the same load，the lateral friction along the pile remain unchanged，or at least very little. It makes relative theoretic analysis and discussion of the influencing factors on pile lateral friction in view of the results of the experiment.