Fibrosis of hepatic cells is a consequence of various etiologies of serious liver injury. Antifibrotic properties of quercetin extracted from broccoli were detected in mice with liver fibrosis induced by CCl4. These activities were assessed by investigating the liver enzymes ALT, AST, and Alb. Also, biochemical markers: TGFβ-1, HA, IL-6 level, and immunohistological markers PCNA and α – SMA analysis were observed and then compared and statically represented. A randomized controlled trial was applied on 21 mice that were grouped into 3 groups. The control group received water and standard feed. A positive control group took CCl4 (0.5μl/g) only. Therapeutic group took CCl4 (0.5μl/g) then quercetin (50mg/kg). Increases in ALT, AST, and biochemical markers (TGFβ-1, HA, IL-6) activities and decrease in Alb were observed in mice who received CCl4 only, in contrast to mice that took quercetin after CCl4 administration with statistically significant value p<0.001. After receiving quercetin, the immunohistological investigation assessed α –SMA downregulation, which certain ECM accumulation, but a renewal of fibrotic liver cells was detected with the raise of the regenerative marker PCNA within the liver cells. Quercetin extracted from broccoli may assist in the therapy and improving the recovery of the fibrotic liver.