Here, we found that high mechanical tension significantly increased cell apoptosis ratio and caspase-3 activity, up-regulated gene/protein expression of Bax, caspase-3, cleaved caspase-3, and cleaved PARP, and down-regulated gene expression of Bcl-2 in AF cells compared with the low mechanical tension and control group, indicating that high mechanical tension promotes AF cell apoptosis compared with the low mechanical tension. This evidence concerns the gene CASP3 and atrial fibrillation.