The invention discloses a distribution network line loss abnormal positioning portable device comprising a first rigid box body, a second rigid box body, a third rigid box body, a fourth rigid box body, a metering box body, and one or more telescopic box bodies selected from a first telescopic box body, a second telescopic box body, and a third telescopic box body. A first current and voltage acquisition device is arranged in the first rigid box body. A second current and voltage acquisition device is arranged in the second rigid box body. A third current and voltage acquisition device is arranged in the third rigid box body. A voltage measuring probe is arranged in the fourth rigid box body. An electric energy meter and a data acquisition and communication device are arranged in the metering box body. According to the distribution network line loss abnormal positioning portable device, the operation mode of an existing line is not required to be changed and the distribution network line loss abnormal positioning portable device can be installed without breaking a line. The appearance of the distribution network line loss abnormal positioning portable device is similar to that of an ordinary meter box, and a difference in appearance is insensible. The distribution network line loss abnormal positioning portable device has a good warning effect on authorized opening so as to ensure data accuracy.