In P2P systems, evaluation of trustworthiness of the peers is very important for a safe communication. In order to decide the peer trustworthiness different parameters are needed. In this paper, we propose two fuzzy-based peer trustworthiness systems for JXTA-Overlay P2P platform. In the first system, we considered two parameters: Actual Behavior Criterion (ABC) and Reputation (R). In the second system, we took in consideration three parameters: Actual Behavior Criterion (ABC), Mutually Agreed Behavior (MAB) and Reputation(R). We compared the performance of the proposed systems by computer simulations. The simulation results have shown that in general the system with three parameters has better performance, but the complexity is higher.