Security is an essential requirement in mobile ad-hoc networks to provide protected communication between mobile nodes.Due to unique characteristics of MANETs,it creates a number of consequential challenges to its security design.To overcome the challenges, there is a need to build a multifaceted security solution that achieves both broad protection and desirable network performance. MANETs are vulnerable to various attacks, black hole, is one of the possible attacks. Black hole is a type of routing attack where a malicious node advertise itself as having the shortest path to all nodes in the environment by sending fake route reply. By doing this, the malicious node can deprive the traffic from the source node.I proposed a TDSDV (Trusted DSDV)Protocol to prevent security threats of black hole by notifying other nodes in the network of the incident.This book emphasis on the behavior of the Black Hole node & its prevention using trusted proactive routing. Considering different scenarios various performance parameter before & after attack is analyzed using simulator.