Objective To investigate the effect of resveratrol (Res) on microglia function after intracerebral hemorrhage (ICH) and its possible mechanism. Methods (1) Animal experiment: 27 SD rats (12-week-old) were randomly divided into 3 groups (9 each): control group, ICH group and Res group; each group was randomly divided into three subgroups (3 each) at 6 h,24 h and 72 h after operation. Rats in ICH group were modeled by autologous blood modeling method, while in control group were only injected with needles without autologous blood injection. Rats in Res group were intraperitoneally injected with 50 mg/(kg.d)resveratrol on the basis of ICH group, and 2% dimethyl sulfoxide (DMSO) solvent of the same volume were injected in control group and ICH group. 6 h, 24 h and 72 h after successful modeling, the corresponding rats were subjected to modified neurological severity score (mNSS). Then the rats in each subgroup were sacrificed and their brain tissues were taken from the same area and embedded in wax blocks. The expression of TRL4, CD36, HO-1 and Nrf2 protein in rat brain tissue was observed by tissue section, HE staining,Nissl staining, TUNEL staining and immunofluorescence method. (2) Cell experiment: BV2 mouse microglia cells were divided into control group, Fe²⁺ group (FeSO₄ 10 μmol/L) and Fe²⁺+low dose resveratrol (25 μmol/L) group and Fe²⁺+high dose resveratrol(50 μmol/L) group. The expression levels of TLR4, CD36, Nrf2, p-Nrf2, and HO-1 proteins were detected by Western blotting after incubation for 24 h and 72 h, respectively, and the localization of Nrf2 protein was observed by cell immunofluorescence. Results (1) mNSS score indicated that rats in ICH group had obvious neurological dysfunction while normal in control group. mNSS score of rats was significantly higher in ICH group than in control group (P<0.01). As time went by 24 h or 72 h, mNSS score of rats reduced significantly in Res group than in ICH group (P<0.05, P<0.01). HE staining of rat brain tissue indicated that increased infiltration of red blood cells and inflammatory cells were in ICH group, and the infiltration of red blood cells and inflammatory cells in the brain tissue of rats in Res group was improved compared with those in ICH group. Nissl staining of rat brain tissue showed that, compared with the control group, the dissolution of nissl corpuscles in brain tissue of ICH group increased, and in Res group decreased. TUNEL staining of rat brain tissue showed that the neurocyte apoptosis index in brain tissue of rats in ICH group increased significantly compared with that in control group (P<0.05), and it was significantly lower in Res group compared with ICH group (P<0.05). The immunofluorescence of proteins indicated that the expressions of TLR4, CD36, Nrf2 and HO-1 protein in rats'brain tissue in ICH group increased significantly compared with rats in control group (P<0.05). Compared with rats in ICH group,the expression of TLR4 protein in brain tissue of the rats in Res group decreased at the same time point (P<0.05), while the protein expressions of CD36, Nrf2 and HO-1 increased significantly (P<0.05). (2) Compared with the control group, the relative expression of TLR4, CD36 and HO-1 protein in BV2 cells of Fe²⁺ group increased (P<0.05), the expressions of Nrf2 and p-Nrf2 increased at 72 h (P<0.05), the expression of Nrf2 protein in the nucleus increased (P<0.01); Compared with the Fe²⁺ group, the expression of TLR4 in the low dose group of Fe²⁺+Res and the high dose group of Fe²⁺+Res decreased (P<0.001), and the expression of CD36,HO-1, Nrf2, p-Nrf2 and nuclear Nrf2 protein increased (P<0.05). Conclusions Intraperitoneal injection of resveratrol can improve the neurological function of rats after ICH. The microglia activated by Fe²⁺ within 72 hours after intracerebral hemorrhage mainly showed pro-inflammatory function. Resveratrol may regulate Nrf2/HO-1 signal pathway and promote the transformation of microglia function to anti-inflammatory after ICH.