This paper presents the development of a novel nuclear radiation monitoring and detection system. With the lightweight and global positioning features, the implemented wireless nuclear detection node can easily be deployed to discover unusual or abnormal radioactivity and map the events. ZigBee-based multi-hop mesh communication is adopted between nuclear detection nodes. All wireless nuclear detection nodes are designed with two working modes, continuous operation and timing operation. The two modes can be switched at any specified time to save energy consumption. Meanwhile, the features of anti-jamming against 802.11 network of ZigBee technology are tested and evaluated.