Abstract: Objective To achieve the goal of polio-free in China,according to Ministry of Health arrangement,OPV "mopping up".Methods Immunization campaign was performed in NingXia in January,March and April of year 2000 respectively.The campaign adopted vaccinating all children age below 9 one by one and home by home,while scanning AFP cases onset from 1998 in county and above hospitals and vaccination spot,all found AFP cases would be checked and diagnosed by expert.Results There were 53111 peoples involving in the three rounds "mopping up" immunization,2808860 children should be vaccinated in the three rounds,actually 2772577 children vaccinated;average vaccination rate was 98.71%.The amount of zero dose OPV resident children decreased from 2.10% in first round to 1.06% in seco nd round.On the spot,rapid evaluated result coincided with reported vaccination rate.There were 112 suspected AFP cases found out,68 out of cases confirmed.Conclusion From now on,we should emphasize the report work and improve the quality of the report of AFP cases,perfect the AFP surveillance system.