Plastic pollution is a growing global concern. The ingestion of plastics debris has become one of the biggest threats to marine life. Here we report for the first time the ingestion of meso- (5.1–25 mm) and microplastic (<5 mm) particles by the sea anemone Bunodosoma cangicum, the most abundant species at the Amazon coast, wider Caribbean region (WCR). Ninety anemones (30 at each local) were randomly sampled, during October 2018, in three beachrocks of intertidal zones distributed on the Amazonian coast (state of Pará, Brazil). The individuals were measured (pedal disc diameter, mm) and the contents of the gastrovascular cavity were extracted and analyzed under stereoscope. The identified plastic particles were counted, classified, measured and photographed. Laboratory procedures were performed to prevent airborne fibers contamination. Polymer identification are in course and will be presented. Here, we present the results for a single location (Salinópolis municipality). Overall, 121 microplastics and 2 mesoplastics items were identified in 25 individuals (83.3%) among the 30 examined. On average, 4.1 ± 3.9 plastics per individual were found. Fibers comprised about 89% of the ingested plastics, followed by fragments (~7%) and films (~3%). The particles diameter ranged from 0.09 to 7.6 mm. Linear regression analysis indicated a positive correlation between pedal disc diameter and number of plastic particles (F(1,22) = 6.342; p = 0.01957; r² = 0.2238). No significant correlation (F(1,121); p = 0.2439) was found between pedal disc diameter and plastics diameter. This study provides the first evidence of microplastic contamination of marine invertebrates from the Amazon coast. Abundant species like B. cangicum has the potential to monitor the levels of plastic contamination at the area, which is part of the WCR.