Greenhouse-grown vegetables are often susceptible to infestation by small insect pests, with entry points often becoming vulnerable breaches. This high-density insect-proof door is specifically designed to address the lack of effective insect-proofing solutions for single-building greenhouses. Constructed from durable stainless steel and welded into a robust, integrated structure, the door offers both longevity and convenient access for agricultural machinery. It features a specialized opening and closing mechanism (handle) that allows for further tightening of the inner and outer frames once closed, achieving a high degree of insect exclusion. The door's 1.8-meter inner diameter accommodates the passage of agricultural machinery. Additionally, it can be seamlessly integrated with various sizes of circular galvanized pipes (1-2 inches) commonly used in greenhouse construction.