Concerning the problem that high rate-distortion loss to the encoder caused by the existing watermarking algorithm, combined with the Versatile Video Coding (VVC) standard, a video watermarking algorithm based on the parity of intra frame prediction modes was proposed. Firstly, the first round of rough selection was performed to calculate 35 even-numbered angle modes and select 6 modes from them. Secondly, during the second round of rough selection, whether to calculate the odd-numbered modes of second round rough selection was determined according to the binary watermark state. Thirdly, when Matrix weighted Intra Prediction (MIP) and the Most Probable Mode (MPM) candidate list were performed, whether to calculate the odd- or even-numbered modes was determined according to the binary watermark state. Finally, the mode with the smallest rate-distortion cost was selected as the optimal mode to complete the watermark embedding, and the watermark was extracted by the decoder according to the parity of the received 4×4 block prediction mode. Experimental results showed that when embedding wartermark in 9 video sequences, compared with the algorithm of the original encoder, the Peak Signal-to-Noise Ratio (PSNR) of the proposed algorithm was decreased by 0.005 4 dB on average, the bit rate was increased by 0.07% on average, and the watermark capacity that could be embedded per frame was 625 b on average; compared with the algorithm that embedding the watermark in the parity of the prediction mode, the PSNR of the proposed algorithm was reduced by 0.005 4 dB on average, the bit rate was improved by 0.06% on average, and the total watermark capacity that could be embedded was 3 183 b on average, while the comparison algorithm had the PSNR reduced by 0.035 dB on average, the bit rate increased by 1.12% on average, and the total watermark capacity that could be embedded was 10 309 b on average. It can be seen that the loss of the rate-distortion performance of the proposed algorithm is less than that of the comparison algorithm.