Abstract: Introduced breeding of microbe paraffin inhibitor, property examine in laboratory and in-situ experiment of paraffin inhibitor. microbe paraffin inhibitor AD-4 was a field usable microbe, which composed of microbes tame from field profit and capability, optimize, select from laboratory. Experiment indicate that AD-4 can decrease freezing point of wax to 4~8.5℃ by its emulsify and degradation capacity, decrease surface tension of crude oil cultivation liquid to 30.3%~49.3%,and decrease viscosity to 35%~50%,improved flow properties of crud oil. Applications in 12 wells showed that AD-4 depressed electric current and loading of well, prolonged pump inspection period to tow times in some wells, and ratio of input/output can reached to 1:28.