Mobile ad-hoc network (MANET) is an infrastructure-less, self-organizing and autonomous network with the advantage of being low-cost and having on-demand setup. Its inbuilt unique characteristics like self-organization, frequent topology change, the high mobility of nodes, and resource scarceness make Quality of Service (QoS) routing is an exigent task. Congestion arises in the networks with constrained resources. Unfair distribution of traffic density is one of the reasons of congestion in the network and leads to higher packet losses, additional delay and earlier battery exhaustion on certain nodes. Link breakage due to node mobility and limitation of mobile node's energy are other key factors which make it difficult to design & develop QoS routing in MANET.To overcome these issues, we propose an energy efficient Quality of service (QoS) routing for uninterrupted communication from source to the destination node using Mobile software agent (MSA) paradigm. Software Mobile agents collect and calculate queue length, stability of neighbour nodes, remaining battery power and queuing delay of each node. Finally, the route is calculated based on the estimated parameters. This protocol is highly efficient for balancing load and discovering stable route meeting the delay needs. In this research study, we provide a summary of existing proposal, their key ideas, and our proposal also a simulation study of DSR Routing (Dynamic Source Routing ) and modified DSR using Matlab simulator on the basis of shortest path, Path hop and average trust value of path.