Callistemon citrinus is a medicinal herb of the Myrtaceae family. It is commonly known for brush-like flowers, spiked flowers and attractive, papery bark shaggy, dark-grey and long fibrous strands. It is distributed in moist conditions and thrives on regular watering. These flowers and leaves are droopy and multi-trunked without any thorns. Osteosarcoma, a bone cancer, typically affects long bones of arms and legs, but can occur in any bone. The plant is traditionally used in the treatment of skin infection (scabies, blotch, herpes and eczema) and cancer (carcinogenesis, Colorectal Cancer, osterosarcoma) etc. The study is aimed at unveiling the ethnobotanical description and phytochemical, anti-oxidant, anti-inflammatory, anti-microbial activities and to investigate the cytotoxic and anti-cancer potential of Bottlebrush bark extract on bone cancer cell lines through an in vitro study of C. citrinus. The objective of the study was to explore the antioxidant, antimicrobial and anticancer potential of Callistemon citrinus (Red Bottlebrush) bark extracts in a bone cancer cell line. © 2025 Elsevier B.V., All rights reserved.