Background: Musa seminifera Lour is a tree-like perennial herb that has been used in folk medicine in Bangladesh to heal a number of ailments. Objective: To evaluate the antioxidant, analgesic, antidiarrheal, anthelmintic activities, and general toxicity of the ethanol extract of the roots. Materials and Methods: The extract was assessed for free-radical-scavenging activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, total phenolic content (TPC) by the Folin Ciocalteu reagent, antioxidant activity by the ferric reducing power assay, analgesic activity by the acetic acid-induced writhing and hot-plate tests, antidiarrheal activity by the castor oil-induced diarrhea model in mice, anthelmintic activity on Paramphistomum cervi and Haemonchus contortus, and general toxicity by the brine shrimp lethality assay. Results: The extract showed free-radical-scavenging activity with an IC 50 value of 44.86 μg/mL. TPC was 537.89 mg gallic acid equivalent/100 g of dried plant material. It showed concentration-dependent reducing power, and displayed 42.11 and 69.32% writhing inhibition at doses of 250 and 500 mg/kg body weight, respectively. The extract also significantly raised the pain threshold at the above-mentioned dose levels. In vivo antidiarrheal property was substantiated by significant prolongation of latent period and decrease in total number of stools compared with the control. The LC 50 against brine shrimp nauplii was 36.21 μg/mL. The extract exhibited dose-dependent decrease in paralysis and death time of the helminths. Conclusion: The above results demonstrated that the plant possesses notable bioactivities and somewhat supports its use in folk medicine.