This study included the separation and diagnosis of anthocyanin compounds and testing the antioxidant activity and biological activity on two types of bacteria that infect plants (Pseudomonas savastanoi, Acrobacterium tumfaciens) from the methanolic extract that was prepared using the continuous extraction device (Soxhlet) The anthocyanin compounds were diagnosed using a high-performance liquid chromatography device HPLC. The results showed that the flowers of the Hibiscus Sabdarriffa L contain four anthocyanin compounds (peonidin, malvidin, delphinidin, cyanidin). The biological activity showed a high inhibitory effect against Acrobacterium tumfaciens bacteria at a concentration of 100 mg/cm3 20 mm, while the highest inhibitory amount was against Pseudomonas savastanoi bacteria at a concentration of 400 mg/cm3 with 15 mm compared to some antibiotics. The antioxidant activity showed the methanolic extract had an anti-oxidant effect of 186.787 μg/ml at a concentration of 500 μg/ml and was less effective by 7.232 μg/ml at a concentration of 125 μg/ml compared to ascorbic acid.