This document is a case study report on the restoration and development of Belum Rainforest Resort in Malaysia using symbiosis theory in architecture. It discusses how the resort was developed in two phases to blend built structures with the natural environment in a sustainable way. The report examines how symbiosis theory influenced the planning, design, material selection, and construction of the resort to minimize environmental impact and create harmony between the building and surrounding nature. It analyzes several examples of how on-site materials were reused and open spaces incorporated symbiosis principles of linking opposing elements in a balanced way. The case study aims to demonstrate how applying symbiosis theory can help achieve long-term sustainability in large-scale resort developments.