The scattering and absorption of suspended particles in water severely restrict the quality of underwater imaging. Several works have been proposed to improve the dehazing effect, but their efficiency was not considered. However, the processing efficiency of dehazing is an important indicator of the computing cost in an active application. An improved dehazing method that analyzes and optimizes the estimation accuracy of polarization parameters in the traditional underwater polarization imaging model is proposed. The degree of linear polarization of the target object light and the backscattered light and the transmission coefficient in the scattering medium are jointly estimated by the stochastic gradient descent method. The experimental results indicate that the proposed method can better preserve image details at a faster speed than the traditional underwater dehazing imaging method, especially in high-turbidity water environments. The average speed of the algorithm for restoring a 1024 × 768 pixel image is about 6.2 ms.