A screening method and a risk evaluation method for concerned problems on in-operation nuclear power plant lifecycle management are disclosed. The screening method comprises the following steps: in step S1, all power plant problems Q1-Qn are collected; in step S2, steps from S3 to S6 are performed for each power plant problem Qi; in step S3, whether a preventive maintenance and solving strategy for the power plant problem Qi exists in a database is checked; if yes, a first screening standard is met; in step S4, the power plant problem Qi is subjected to consequence analysis; if the power plant problem Qi is a problem about known equipment with unacceptable consequences, a second screening standard is met; in step S5, predicted fund investment for solving the power plant problem Qi is calculated; a third screening standard is met if the predicted fund investment exceeds a preset amount of money; in step 6, if the power plant problem Qi meets one of the first standard and the second standard or only the third standard is met, the power plant problem Qi is determined as a concerned problem. According to the screening method and the risk evaluation method, possible consequences caused by the problems and costs for solving the problems are considered in concerned problem screening operation, the method is high in universality, and the concerned problems can be screened out in a simple and effective manner.