In the present research work, the effect of praziquantel a nd garlic extract Allium sativum for the control of Clinostomum sp. metacercariae (a trematode) in Apistogramma sp. was evaluated. The study was conducted at the Amazon Research Center for Ornamental Fishes (ARCOF). The experimental population consisted of 48 Apistogramma sp. fish with an average weight of 6 ± 2 g and an average standard length of 8 ± 1.5 cm. The fish were extracted from the experimental ponds of the Research Center and placed in 24 experimental units, with two fish each, containing 3L of water. The Apistogramma sp. fish were infested with Clinostomum sp. metacercariae in the dorsal and anal fins. Two treatments were used in the study: praziquantel and garlic extract, each with different doses. Praziquantel doses were T1: 80 mg/L, T2: 100 mg/L, T3: 120 mg/L, and T0: Control, while garlic extract doses were T1: ...