Wood, a natural material with versatile industrial applications, faces limitations such as low dimensional stability and decay resistance. To address these issues, there has been significant progress in wood modification research. Oil heat treatment has emerged as an effective method among environmentally friendly wood treatment options. Studies have indicated that treating wood with hot vegetable oils yields superior properties compared to traditional methods involving gaseous atmospheres, which is attributed to the synergistic effect of oils and heat. This comprehensive review investigates the physical, chemical, and mechanical modifications induced by the oil heat treatment of wood, along with its impact on biological durability against biotic agents. The review synthesizes recent research findings, elucidates underlying mechanisms, and discusses the implications for wood material science and engineering.