Abstract: Reducing the rebound rate of shotcrete can promote the efficiency of support and reduce the risks of collapse and rock burst for underground openings. To evaluate the effect of nanometer scale admixture (NSA) and macro synthetic fiber (MSF) on the rebound rate of wet-mix shotcrete (WMS), rebound rates were compared with each other based on wet sprayed technology among WMS with different cementing compositions such as introducing NSA or silica fume. The contents and fineness of NSA were also investigated when taking rebound rate as the main subject. Contents, aspect ratios and hybrid ways of MSF were discussed, too. The results indicated that NSA could reduce the rebound rate of shotcrete. The rebound rate of WMS could be reduced by about 17% to 25% when silica fume was replaced by NSA totally. Besides, the rebound rate of WMS would further decrease with the increment of contents or fineness of NSA. Macro synthetic fiber had a part in reducing rebound rate. Although fiber nature had little effect on rebound rate, the aspect ratio and content of MSF couldn't be ignored, and its best values were 38 and 10 kg/m³, respectively. In addition, the rebound rate could be further reduced when WMS was optimized with hybrid MSF consisting of two kinds of fibers, whose aspect ratios were 76 and 30.