Metallic biomaterials have been used to repair and replace human body parts because of their excellent biocompatibility, strong corrosion resistance, and high mechanical properties. A ceramic biomaterial that is highly suitable for coating on metallic biomaterials is hydroxyapatite. This is because it is biocompatible with synthetic and natural bone tissue. There has been a growing interest in HAp-based coatings using thermal spray techniques to enhance the crystallinity and adhesion quality and produce a dense coating of metallic biomaterials. Thermally sprayed coating material has been studied and reviewed in detail in the bioactivity analysis and electro-corrosion analysis. Furthermore, the bioactivity of HAp coatings is determined by their ability to promote bone formation and osseointegration and a valuable understanding of the mechanisms and current advancements in bioactivity. Additionally, the corrosion behaviour of thermally sprayed HAp coatings under simulated conditions has been reviewed.