The invention relates to a single-phase electric energy meter on-site tester, which comprises a split type current transformer, a voltage transformer, an electric energy metering chip, a single-chip microcomputer, a photoelectric sampler, a liquid crystal displayer, a keyboard and a micro printer. The split type current transformer is a split-type precise current transformer, the measuring range of which is 50 A. The voltage transformer is a 220V precise voltage transformer. The electric energy metering chip is an ADE7755 chip; the single-chip microcomputer is an AT89S51 single-chip microcomputer; the photoelectric sampler is an adsorption-type photoelectric sampler for detection of an electric energy meter; the liquid crystal displayer is a character liquid crystal display LCD1602; the keyboard is a determinant keyboard having 16 keys; and the micro printer is an embedded minitype thermal printer having a TTL serial port. The single-phase electric energy meter on-site tester is reasonable in design, is high in detection precision, and can realize on-site test of each single-phase low-voltage energy meter without cutting off the power or dismounting wires.