Abstract: Agricultural industry technology innovation alliance is more complex than other industries because agricultural technology innovation has some characteristics as follows: strong public welfare，longer R&D cycle， high risk and strong reproduction. Based on the current situation of development of agricultural industry technology innovation alliance in Guangdong province，this paper explores the organization mode，operation mechanism and existing problems of agricultural industry technology alliance and suggests that the government should specially plan for the development of agricultural industry technology innovation alliance，cultivate and support those alliances led by leading enterprises，evaluate the positive externalities of agriculture in different industrial technology by building reasonable evaluation system，finance the optimal investment proportion for various categories and build a good mechanism for internal benefit sharing and risk sharing.