The development of landscape architecture is in full swing, and its renewal is being given a heavier task in the historical process. Based on the philosophical basis of physiology, the clustering elements of landscape architecture as well as the internal logic of ideology, science and technology, humanities and art expression, are sorted out. The essence of “function” based on the harmonious relationship between heaven, earth and man is deduced, and the core support of landscape architecture as the foundation of “engineering” is revealed. On the basis of clarifying the origin, it derives the cognitive pattern, creative motive mechanism and development way that landscape architects should hold, namely, excavating ideological creation, exerting function to guide the creation and releasing engineering technology creation. Thus, the author tries to define the objective, scientific and clear core of landscape architecture.