Intrusion detection in wireless sensor network (WSN) has been a critical issue for the stable functioning of the networks during last decade. Wireless sensors are small and cheap devices that have a capacity to sense actions, data movement, and communicate with each other. It is a self-governing network that consists of sensor nodes deployed in a particular environment, which has wide applications in various areas such as data gathering, military surveillance, transportation, medical system, agriculture, smart building, satellite communication, and healthcare. Wormhole attack is one of the serious attacks, which is smoothly resolved in networks but difficult to observe. There are various techniques used to detect the malicious node such as LITEWORP, SAM, DelPHI, GRPW, and WRHT. This chapter focuses on detection methods for wormhole attacks using trust-based systems in WSN.