Peer-to-Peer Lending (P2P) applications were developed as an alternative funding solution, mainly for small-medium enterprises. P2P can also be a promising alternative investment instrument. The significant gap between the number of lenders and borrowers is as a major issue that has been identified in the P2P of Indonesia. Therefore, the analysis of factors affecting willingness to lend in P2P lending needs to be done. The purpose of this study is to identify the socioeconomic characteristics of lenders, lenders perspective on familiarity, service quality, security protection, borrowers’ reputation, borrowers’ information, perceived benefits, perceived risk, trust to the borrower, trust to the intermediary, and willingness to lend in P2P lending applications. A total of 109 respondents filled out online questionnaires distributed through several media with the criteria of Indonesian citizens with investment experience in P2P. Descriptive and crosstab analysis was applied in this study. Based on the result, the impression that the borrowers will keep their promises (TB3), the system/ policy applied in the P2P platform to protect the interest of lenders (TI 2), the sense of security upon making transactions in P2P (SP 1), more attractive investment returns (PB 3) and quality assurance of prospective borrowers (SQ 4) are the most important factors affecting lenders willingness to lend.