Abstract: For the problem of coverage blind area generated by randomly deploying the heterogeneous nodes in the initial stage, and inspired by simple random sampling in probability theory and optimization algorithm, a coverage optimization algorithm for heterogeneous sensing radius in Wireless Sensor Networks (WSNs) is proposed. To minimize the sensor nodes moving distance and improve the coverage rate, a quadratic programming mathematic model is established according to the relationship between coordinates of the intersections that between the sensing circles and the sampling line segments. Meanwhile, the coverage of plane will be optimized when more line segments get optimizing coverage. Simulation results show that the algorithm improves the coverage rate of homogeneous networks effectively.