The sensor for two-phase flow measurements is installed between two sections of pipe, providing an accurate measurement of radial temperature gradient in a two-phase flow. The sensor includes a heated tube having axially opposed first and second open ends. An annular sensor mount is secured about the first end thereof. First and second annular flanges are mounted to the heated tube for fluid-tight connection with the pair of pipe sections such that a two-phase fluid flowing through the pair of pipe sections continuously flows through the heated tube and a circular opening defined by the annular sensor mount. A central temperature sensor is suspended centrally within the circular opening for measuring a central temperature of the two-phase fluid. At least one peripheral temperature sensor is mounted on the annular sensor mount adjacent an inner annular wall thereof for measuring the peripheral temperature of the two-phase fluid.