As a strong supplement of bulk power system, microgrid has become an important part of smart grid and has wide prospects in residential application. The increasing penetration of renewable energy and electric vehicles has bring numerous challenges to the stability of microgrid system. The stable and economic dispatch strategy plays a major role in the operation of such a distributed power system. This paper presents a robust economic dispatch strategy for residential microgrid. Considering the worst scenario of available wind power, this strategy schedules EV charging load, outputs of distributed generators for the sake of reducing operation cost under variable practical constrains such as power balance constrain, EV charging constrains and constrains of distributed generators. A charging time based grouping dispatch approach is proposed to schedule the charging of numerous electric vehicles. Numerical results show that the proposed dispatch strategy is robust and reliable.