Mitigation algorithm against black hole attack using Real Time Monitoring for AODV routing protocol in MANET Adhoc On Demand Vector (AODV) is a demand driven routing protocol in Mobile Ad hoc Network (MANET). There is always a resource constraint in adhoc network and threat from malicious nodes and hence feasible solution is preferably needed. For this reason, in this paper, we propose a new method RTMAODV (Real Time Monitoring AODV). It does not introduce any overhead. Moreover neighbor node detects and prevents black hole attack using real time monitoring. The new proposed method is effective for multiple sessions. The concept of broadcasting is being used in the method. Node which replies to RouteRequest (RREQ) by source is being monitored in promiscuous mode. Detection of malicious node is actually done by neighbor node of RouteReply (RREP) sender node. In simulation, new method has shown outstanding result in terms of packet delivery ratio as compare to AODV routing protocol in presence of malicious node under black hole attack.