Abstract: Taking the waxy oil from Bohai Oilfield as an research target, experiment to measure oil viscosity at different pressures and water cut is made through adopting high-temperature and high-pressure rheometer, and influence of pressure on wax deposition course and wax deposition point of oil-water mixer is investigated.Results show that viscosity-temperature curve of oil-water mixer at different pressures agrees to the exponential law, and meanwhile。oil viscosity with pressure also appears exponential relationship.When pressure increases from 0.1 MPa to 12.0 MPa, wax deposition point raises linearly with pressure。and mean increase range is about 0.1 ℃/MPa; at a same pressure, mean deviation of wax deposition point at different water cut is 0.2 ℃, which shows that water cut has a slight impact on wax deposition point of Bohai waxy crude oil.