The invention relates to a frame-level application layer dynamic FEC coding method. The method comprises: utilizing a video transmission system, on a sending end, a video sequence firstly passing through an H.264 video encoder, setting a quantization parameter (QP) value, compressing each frame of video image into different numbers of source data packets by the video encoder, dividing the source data packets of each frame into one group by FEC encoding, generating a certain number of redundant packets are generated by using a forward error correction encoding algorithm, and the source data packets and the redundant packets forming an FEC encoding group. The receiving end can recover the source data according to the corresponding error correction decoding algorithm. According to the invention, based on principle that the I frame and the P frame have the same importance in video decoding, and the FEC performance of a large number of coding packets or low code rate is better, the code rate of I frames with a large number of packets is improved, redundant packets are allocated to P frames with a small number of packets, and the P frames with different numbers of packets have differentcode rates, so that the decoding effects of the I frames and the P frames are equivalent, consistent importance is achieved in decoding, the average peak signal-to-noise ratio (PSNR) of a video is improved, and the overall quality of the video is improved.