Comparative molecular field analysis (CoMFA) techniques were used to perform three-dimensional quantitative structure-activity relationship (3D-QSAR) studies on the anti-tumor activity (pIH and pIC) of 28 fluoroquinolon-3-yl s-triazole sulfide-ketone derivatives (FQTSDs) against two cancer cell lines, including human hepatoma Hep-3B cells and human pancreatic cancer Capan-1 cells. 23 compounds were randomly selected as the training set to establish the prediction models, which were verified by the test set of 6 compounds containing template molecule. The obtained cross-validation (Rcv2) and non-cross-validation correlation coefficients (R2) of the CoMFA models were 0.477 and 0.850 for pIH, and 0.421 and 0.836 for pIC, respectively. The contributions of steric and electrostatic fields to pIH were determined to be 48.1％ and 51.9％, and those to pIC were 49.4％ and 50.6％, respectively. The CoMFA models were then used to predict the activities of the compounds in the training and testing sets, and the models had a strong stability and good predictability. Based on the 3D contour maps, four novel FQTSDs with a higher anti-tumor activity were designed. However, the effectiveness of these novel FQTSDs is still needed to be verified by experimental results.