摘要： 税法在体系上虽被划入公法，但它在内容上和实体上仍和私法有着千丝万缕的密切联系。本文认为，建立征税行为的无因性理论对于诠释财税法与私法调整的协调问题有着重要的意义。当事人的行为或其经济结果只要满足税法规定的征税要素，就应当纳税，而不论该行为的私法效力如何。但该经济行为的经济后果已被其他职能部门确定为应加以全部返还或者应予以没收，则不应再征税，已征税款应予返还。

关键词: 征税行为 , 税收无因性理论 , 税收公平原则

Abstract: Though tax law is classified into the scope Of public law，it’s substantiVe contents in fact is closely related with private law．This paper tries to develop abstract theory’of act in imposing taxes，the act of imposing taxesis not subject to tax payers’effectiveness under private law．Whether the act of parties in question is Valid，or is of defects will not affect the exercise of taxation．power of tax authorities．

Key words: Tax-imposition act, the abstract theory of tax, the principal of tax equity