This research introduces a new creative voluntary service “Pro Bono”，which based on professional skill and professional responsibility. This is an exploratory research on Pro Bono and its future. Comparing Pro Bono with three current volunteer service models，I find out these features of Pro Bono：Pro Bono is based on professional skill and professional responsibility，it’s more professional；Pro Bono serves organization but not individual；Pro Bono helps NGO’s capacity building directly and help solve kinds of social problems indirectly. As its great value，this research recommends that Pro Bono should be spread. Basing on the new institutionalism in sociology and organization theory，I anylze the current environment and put forward some advices. Strengthen the industry associations’ role in supervising and exciting corporations fulfilling their social responsibility，strengthen government policy advocacy on Pro Bono，strengthen public opinion’s encouragement on NGOs and corporations that are doing Pro Bono to promote the cognition and practice of Pro Bono，and achieve organizational isomorphism to make Pro Bono its development through the institution pressure and imitation mechanism in the end.