The graft copolymer of superfine fiber and acrylamide used to profile control and water plugging was optimized through the indoor experiment, the best formula of profile control agent was as follows: 2000mg/L graft copolymer C-PAM +1000mg/L cross-linking agent PF+ 20mg/L ammonia chloride control agent. Salt resistance, temperature tolerance and shear resistance of the profile control agent were studied systematically. The results showed that, the profile control agent had good salt resistance, its initial viscosity in tap water was of 30mPa·s, and after gelation, its viscosity was of 3.5 × 10⁴mPa·s，and in simulated formation water with salinity of100 g/L, the viscosity of the profile control agent after gelation could be as high as 3 × 10⁴mPa·s. The profile control agent was suitable for the neutral oil reservoirs with the formation temperature of 60数80℃, which could be stable for more than 80d. The profile control agent had good shear resistance, the retention rate of initial viscosity was over 60% after high speed shear -ing at the shearing rate of 100 s^-1, and the retention rate of the gel strength was above 80% after forming gel. Thus, the graft copoly-mer of superfine cellulose and acrylamide could be used in the profile control and water plugging.