Abstract: The key technology of bottom water horizontal well is to control the bottom water intrusion, ensure formation pressure and enhance oil recovery effectively, extend non-water or low water content oil production at the maximum and maintain bottom water displacement in order to improve the bottom water reservoir development results. Through nitro-gen + gel dual control blocking bottom water technology,gel separators and high pressure gas chamber could be formed in oil-water interface in the bottom water reservoir,which increase the flow resistance, reduce fluid level and can eliminate cone of pressurized water effectively, raise the level of wells recovery. The practical application on-site has proved its validity and reliability. The technology can be widely applied in the oil-water reservoir controlling waterand oil development practice.