A water-swellable rubber (WSR), compatibilized by the amphiphilic graft copolymer, has been prepared by blending chlorohydrin rubber (CHR) with crosslinked polyacrylate (CPA), Poly(vinyl alcohol)-g-poly(butyl acrylate) (PVA-g-PBA), precipitated silica (PSA), and poly(ethylene glycol) (PEG). The WSR was characterized by scanning electron micrography (SEM). The dependence of the water-absorbing ratio by weight, the water-swelling ratio by volume, and the percentage loss by weight on PVA-g-PBA and crosslinked polyacrylate contents was investigated. The effect of PVA-g-PBA and crosslinked polyacrylate contents on second water-swelling behaviors and long-term water-retention behaviors were also studied.