Basing on one generation of individual selective breeding and four generations of family selective breeding of Litopenaeus vannamei, 120 selective breeding families of resistance to WSSV were produced from 2002 to 2007. Experimental WSSV challenging tests showed that the survival rates of generation 2(G2)，G3，G4 and G5 were 5.57±9.83%, 8.66±11.52%, 9.52±8.84% and 13.79±12.86%0%, and the variation coefficient of survival rates were 1.77,1.40,0.97and 0.87, respectively. Each generation of selective breeding families of resistance to WSSV were divided into three groups: relatively high resistant families, mid-resistant families and susceptible families post WSSV infection. The proportion of susceptible families in G2 to G5 were 76.5%, 55.2%, 51.4% and 33.3% ,and the survival rate were 0.44 ± 1.09%,0.78 ± 1.70%,2.27 ± 2.76% and 2.44± 3.09 %,respectively ,with a acute mortality peak appeared at 2nd ~3rd day post infection. The proportion of mid-resistant families in G2 to G5 were 0、20.7%、31.1% and 38.5% ,and the survival rate were 0、9.08±1.46%、10.7±1.41%and 11.36±3.30% ,respectively ,with two mortality peaks appeared at post WSSV infection, and the 1st peak value was greater than that of the 2nd peak. The proportion of relatively high resistant families in G2 to G5 were 23.5%、24.1%、17.1% and 28.2% ,and the survival rate were 22.23±5.21%、22.7±12.30%、24.45±6.56% and 28.98±8.09% ,respectively ,with two mortality peaks appeared at post WSSV infection, and the 1st peak value was less than that of the 2nd peak, which showed that these families in this group possessed strong resistance to WSSV infection. So the eruptible time of WSSV was delayed and the valuable opportunity could be offered to take effective measure to prevent and cure. However, the average of spawning quantity of each generation was declining (p <0.05) year after year.