ABSTRACT This research was conducted out in November 2020-February 2021 at the Laboratory of Fish Quarantine and Quality Control (BKIPM) Pekanbaru, Riau. The aims of this research was to test the activity of A. alba mangrove leaf extracts and stems in inhibiting the growth of pathogenic bacteria P. aeruginosa, A. salmonicida and S. aureus. The research method used in this study is the exp…