B vitamins improve animal performance through promote a wide range of metabolic pathways in animals as cofactors. Therefore, the impact of B-complex vitamin injection on performance, metabolic diseases, hematological parameters, and antioxidant status in pregnant Sannen goats and their newborn kids during the transition period was investigated. The pregnant goats (3 years old) were randomly divided into two groups: control (No B complex vitamins injection) and B complex vitamins (5 ml B complex vitamins injection per animal). B complex vitamins were injected twice intramuscularly into goats, according to the manufacturer's recommendation, during five- and three-weeks prior kidding. To determine the dry matter intake, feed samples were prepared. Also, metabolic diseases in goats and their offspring were recorded during the study. Blood samples of goats and newborn kids were taken seven days after parturition and measured for B vitamins concentrations, as well as hematological and antioxidant parameters. According to the results, the performance (body weight and dry matter intake) of goats and kids improved in B-complex vitamins group compared to the control group (P < 0.05). In addition, metabolic diseases were reduced in the goats and their offspring treated with B complex vitamins compared to the control group during the transition period (P < 0.05). The levels of cobalamin, pyridoxine, thiamine, folic acid, nicotinic, pantothenic, and unconjugated pteridine increased in the plasma of goats and their children by maternal B complex injection than in the control group during the transition period (P < 0.05). Higher (P < 0.05) levels of red blood cells, hemoglobin, hematocrit, total antioxidant status, glutathione peroxidase, superoxide dismutase, and catalase in goats' plasma, as well as red blood cells, hemoglobin, hematocrit, glutathione peroxidase, and superoxide dismutase in kids' plasma treated with B complex vitamins than the control group, were observed (P < 0.05). These results suggest that maternal Bcomplex vitamin injection is required for the improvement of performance, hematological status, and antioxidant status in pregnant goats and their kids.