A greenhouse support type irrigation device comprises a main stream pipe, branch pipes and arched support pipes. Multiple arched support pipes are connected with one of the branch pipes, all the branch pipes are connected with the main stream pipe, the main stream pipe is connected with a water collecting basin, the main stream pipe is provided with a water suction pump, and the arched support pipes are provided with spray holes. The greenhouse support type irrigation device can serve not only as an agricultural greenhouse support, but also as water pipes. For a greenhouse planting area in a plain, the defect that an existing water saving irrigation technique cannot be popularized in a rural area due to high cost can be overcome, and the water saving effect at a high level can be achieved; meanwhile, the manufacturing cost of the greenhouse support type irrigation device is far lower than that of a common water saving irrigation greenhouse, and therefore popularization and application are facilitated.