The capacity that needs to be improved in a woman is one of her main tasks as a mother who educates her children. The Professional Mother Institute (IIP) is a virtual community that empowers women to become professional mothers. IIP has expanded the community to various cities and countries, and has also won many awards. But in the last batch there has been decline significantly in the numbers of members along with applying code of conduct in an effort for IIP members can always participate actively in knowledge sharing. Beside that, as far as we know, no one has discussed the factors that influence knowledge sharing in a virtual community that empowers mothers. Therefore, researchers are encouraged to explore what factors influence knowledge sharing at IIP which uses the Social Networking Sites (SNS) as one of them whatsapp. This research can contribute to IIP by providing input on how IIP makes members keep active in sharing knowledge and keep on increasing. Other than that, this certainly can be a learning for other virtual communities. The method of collecting data in this study used an online questionnaire that was distributed to IIP members of the class 'Bunda Sayang'. This data collection received a response of 115 valid respondents. This data then processed with PLS SEM. The results of this study are perceived reciprocal benefit factors, Perceived enjoyment, Perceived status and Outcome expectation have a positive effect on knowledge sharing in whatsapp group IIP members. Future research can raise other factors or see the impact of knowledge sharing by women in virtual communities, especially those related to community empowerment.