Most of the routing protocols in Wireless Sensor Networks (WSN) generally optimize for limited capabilities. Security is a serious concern. This paper proposes a novel method to bring in security into Destination Sequenced Distance Vector (DSDV) routing protocol. One of the main security issues in DSDV routing is that all nodes are assumed to be trustworthy. This makes the wireless sensor network vulnerable to malicious attacks. Any intruder can send malicious or modified data to the unsuspecting sink, which will be accepted without any checks. In this paper, a secured data integrity check for DSDV protocol has been proposed. The method uses the concept of hashing to achieve data integrity. The performance has been studied with respect to delay, throughput and energy metrics.