In autonomous driving path planning, ensuring the computational efficiency and safety of planning is an important issue. The Dyna framework in reinforcement learning can solve the problem of planning efficiency. At the same time, the Sarsa algorithm in reinforcement learning can be effective in guaranteeing the safety of path planning. This paper proposes a path planning algorithm based on Sarsa-Dyna for autonomous driving, which effectively guarantees the efficiency and safety of path planning. The results show that the number of steps planned in advance is proportional to the convergence speed of the reinforcement learning algorithm. The Sarsa-Dyna will be proposed. The analysis of convergence speed and collision times has been done between the proposed Sarsa-Dyna, Q-learning, Sarsa and Dyna-Q algorithm. The proposed Sarsa-Dyna algorithm can reduce the number of collisions effectively, ensure safety during driving, and at the same time ensure convergence speed.