Abstract: In view of the problems occurred in Chunguang oilfield,such as strong water sensitivity,low temperature low pressure unfavorable for fracturing fluid gel breaking and small reservoir pore throat problems,the experimental research and application of oil-based fracturing fluid was carriedout.Through optimizing oil base fracturing fluid formula suitable for this block,the research solved gel breaking problem within a controlled time under low temperature(30~40℃).The practical application of oil base fracturing fluid in Pai 2-401well achieved the ideal increased production effect.