美国是以所得税为主体的国家，实行联邦税、州（省）税分级管理的税收体制，美国还允许各地设正地方税种，对科技实行减免税收优惠政策，主要体现在以下两个方面：一、把科研机构作为非赢利机构免征税收美因首先在税法上明确非赢利机构不用纳税。其次明确各类科研机构（包括政 The United States is a country that takes income tax as the main body and implements the taxation system of federal tax and state (province) tax grading and administration. The United States also allows local governments to set local tax types and preferential tax relief policies for science and technology, mainly in the following two aspects: , The research institutes as a non-profit institutions exempt from taxes due to the United States first tax law clearly non-profit institutions do not pay taxes. Second clear all types of research institutions (including government