In software-defined wireless sensor networks (SDWSNs), topology control is a fundamental procedure to maintain the global network topology. However, the open wireless channels of SDWSNs make it possible for an attacker to eavesdrop, replay, or modify the topology messages, thus posing a great threat to the network operations. The security of SDWSN topology control has not received enough attention yet. Identity-based cryptography (IBC) may be fitter for SDWSNs due to its capability of generating the public key from the node identity directly, compared with traditional cryptography. In particular, identity-based combined encryption and signature cryptography (IBCES) could encrypt and sign the messages using the same identity. As such, to secure the confidentiality, integrity, and authentication of topology information, we put forward a secure topology control mechanism based on IBCES. First, we use an identity-based encryption authenticated key agreement scheme to implement the authentication of neighbor nodes and hop-to-hop verification via secure neighbor discovery and topology discovery processes. Then through the node admission and key establishment process, the end-to-end secure channels are established between the nodes, sinks, and Controller. Finally, secure topology collection and management processes supporting flat and hierarchical network structures are designed to guarantee the security of topology information. Theoretical analysis shows that our methods could satisfy the security needs of SDWSN topology control and resist several security attacks. The experimental results indicate that our mechanisms are suitable for SDWSNs.