电子串行号（英语：Electronic Serial Number，缩写：ESN），又称ESN码是美国联邦通信委员会规定的，每一台移动设备（例如移动电话、智能手机、平板电脑等）独有的参数，其长度为32位。早在1980年类比式移动电话系统发明时，就已经在使用。1997年后，美国电信行业协会取得了ESN码的管理和授予权。目前ESN码一开始使用于AMPS和D-AMPS手机上，目前则于CDMA手机上最为常见。另一种常见的手机编码IMEI（国际移动设备辨识码）则最常使用在GSM制式的手机上。

Electronic serial numbers (ESNs) were created by the U.S. Federal Communications Commission (FCC) to uniquely identify mobile devices, from the days of AMPS in the United States starting in the early 1980s. The administrative role was taken over by the Telecommunications Industry Association in 1997 and is still maintained by them. ESNs are currently mainly used with CDMA phones (and were previously used by AMPS and TDMA phones), compared to International Mobile Equipment Identity (IMEI) numbers used by all GSM phones.