分时长期演进（英语：Long Term Evolution，Time-Division Duplex ，简称“LTE-TDD”）是基于3GPP长期演进技术（英语：LTE）的一种通讯技术与标准，属于LTE的一个分支。该技术由上海贝尔、诺基亚西门子通信、大唐电信、华为技术、中兴通信、中国移动、高通、ST-Ericsson等业者共同开发。

TD-LTE是LTE-TDD的商业名称，它是由中国移动等主导创立TD-LTE全球发展倡议组织（GTI, Global TD-LTE Initiative）推动支持LTE-TDD标准化与商业化的项目。

LTE (Long-Term Evolution, commonly marketed as 4G LTE) is a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using a different radio interface together with core network improvements. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9.