The crystal structure, physical, chemical and phase transition properties of trititanium pentoxide (Ti₃O₅) have aroused a broad range of research effort since the 1950s. Different crystalline forms (α, β, γ, δ and λ) of Ti₃O₅ exhibit various properties. Particularly, reversible phase transitions between λ- and β-Ti₃O₅ have been attracting increasing research interest, which brings new potential applications of Ti₃O₅ materials in the field of energy and data storage. More recently, Ti₃O₅ materials have shown excellent performance in trace detection, microwave absorption and virus adsorption, which has expanded its application fields. Here, the essential properties of different crystal forms of Ti₃O₅ are described in detail. An intensive overview of Ti₃O₅ preparation methods and applications is comprehensively summarized.