Aiming at the problem of the high computational complexity of the cross-component linear model (CCLM) in versatile video coding (VVC) intra prediction, this paper proposes an improved algorithm,quick cross-component linear model (QCCLM) based on the CCLM technology.First,the position and number of sub-sampling samples are fixed according to copy adjacent available samples to fill unavailable samples,and remove the redundant processes and additional calculation steps;Then,the luminance down-sampling optimization process is used to reduce the types of down-sampling filters;Finally,the derivation process of the linear model parameter β is improved so as to make the prediction model more accurate.The experimental results show that compared with the standard algorithm of H.266,the algorithm saves 0.14% of the code rate on the chrominance component of the test image sequence in the all intra frames configuration,and the total coding time is reduced by 4.05% on average.The algorithm improves coding performance while reducing coding complexity.