Proxy cryptosystem based on time segmentation (PCBTS) is a typical proxy cryptosystem, which can delegate decryption right to the proxy decryptor, thus alleviating the burden of the original decryptor. Although it has broad application prospects, related research results are not plentiful. Identitybased encryption (IBE) applies the user’s identity directly as a public key, thus the management of the public key certificate is simplified. It therefore has attracted many researchers to put forward a large number of schemes in recent years. According to the differences and similarities between the PCBTS and the IBE in the aspects of algorithm structure and security model, we propose a generic construction method for the PCBTS with a proof of its security. Using the proposed method, any secure IBE scheme can be transformed into a secure PCBTS. We apply this method to an actual case and obtain a secure PCBTS in the standard model, which greatly enriches the quantity and type of PCBTS.