The past few years have witnessed a significant progress in the research of underwater acoustic sensor networks. However, most studies on network deployment can only achieve excellent coverage with isolated connectivity or excellent connectivity with coverage holes in the monitoring area. Both coverage and connectivity are important to guarantee the quality of monitoring in Underwater Acoustic Sensor Networks (UASNs). To achieve the joint optimization of network coverage and connectivity, we proposed a deployment optimization mechanism using depth adjustable nodes in UASNs. The sink nodes are evenly distributed on the water surface and act as cluster heads. The sensor nodes in a cluster are adjusted vertically to form the topology with the sink node as the root node so that all nodes in the network are connected. Network deployment is optimized by finding the optimal location of node, with the network topology remains the same as a constraint. Simulation results show that our proposed deployment mechanism can achieve higher coverage with all nodes connected.