根据美国大使馆网页的通知,是最多10年,而不是都是10年。签证的有效期可能会超过护照的有效期。在这样的情况下,可以新旧护照一起使用,不需要再办理新签证。 以下是官方原文。 Chinese applicants who qualify for a B-category nonimmigrant visa (NIV) may now be issued multiple-entry visas for up to 10 years for business and tourist travel. Qualified Chinese students and exchange visitors and their dependents who qualify for F, M, or J-category visas are now eligible for multiple-entry visas valid for up to five years or the length of their program.本回答被提问者采纳