Abstract With the spread of highly functional mobile devices, anyone can send messages in a simple manner. On the other hand, risks regarding the leakage of privacy information have increased in number. Software engineers must prevent the leakage of privacy information caused by problems of software systems. The need to tackle privacy issues in the early stage of the software development cycle is called Privacy by Design (PbD). However, a body of knowledge for privacy friendly software development has not been built. Since software developers are not always privacy experts, to provide such a body of knowledge is significant. This paper proposes a metamodel that manages knowledge for development of privacy friendly software and presents a knowledge base that embodies the metamodel by the already known knowledge. We also show an example using the knowledge base to present its usefulness.