The invention relates to an electric energy meter. A first mutual inductor used for being penetrated by a live wire, a second mutual inductor used for being penetrated by a zero line and a puncture wire clamp used for obtaining a voltage are arranged in a space defined by a base and a meter cover of the electric energy meter, the puncture wire clamp is provided with a first threading hole used forbeing passed through by the live wire and a second threading hole used for being passed through by the zero line, a first entrance hole and a first outlet hole used for being passed through by the live wire sequentially as well as a second entrance hole and a second outlet hole used for being passed through by the zero line sequentially are accordingly formed in two side plates of the base, the first threading hole and the first mutual inductor are located on a first routing path that the live wire passes through the first entrance hole and the first outlet hole, and the second threading holeand the second mutual inductor are located on a second routing path that the zero line passes through the second entrance hole and the second outlet hole. The invention also relates to a meter case provided with the electric energy meter. The live wire and the zero line can directly pass through the electric energy meter, and the voltage can be obtained by virtue of the puncture wire clamp, so that the electric energy meter maintains temperature to be normal, and the probability that the electric energy meter is burned is avoided.