More and more freewares are showing to internet users with the development of the opening and sharing spirit of internet and the improvement of technology and business model. It also brings more intellectual property disputes, privacy violations and unfair competitions. How can freeware operators achieve profitability? Shouldn't freeware operators assume obligations according to the principle of rights and obligations reciprocity? This paper systematically expounded the concept, connotation, way of profit and attribute of freeware, and discussed the legal obligation, contract obligation and legal regulation of freeware operators.