Wireless sensor network comprises of a set of sensor nodes that communicate among each other using wireless links and work in an open and distributed manner because of less number of resources on the nodes. The sensor nodes sense information about an event from the ambiance and then the information is forwarded to a sink node for further processing and analyzing. The sensed information can be forwarded inmanyways, earlier uni cast routing was there to a single sink node,but due to the wide variety of WSN applications the presence of multiple sinks is realized which necessitates multicast routing for efficient data dissemination to multiple destinations. For any disaster surveillance or fire handling emergency scenarios various multicast routing protocols have been proposed by many researchers. This paper focuses on providing a survey of the existing multicast routing protocols by presenting approach, their advantages and disadvantages. Further a comparative study of various multicast protocols is done on the basis of different parameters to identify different issues and challenges that need to be resolved for each one of them.