Stress-reduced GaAs layers were grown on Si substrates with the epitaxial lift-off technique and regrowth by metalorganic chemical vapor deposition. The GaAs thin film was bonded to the Si substrate using SeS2 and another GaAs layer was regrown. The crystal quality is very much improved compared with the conventional heteroepitaxial GaAs-on-Si grown by using two-step growth method. The full-width at half-maximum is as small as 54 arcsec and the slope of the time-resolved photoluminescence decay line corresponding to the minority carrier lifetime is 1.86 ns, The stress involved in GaAs layer is almost zero after the regrowth. The combination of epitaxial lift-off and the regrowth technique is a method to obtain a stress-reduced high-quality GaAs layer on the Si substrate.