To improve a work efficiency of instrumental error measurement by shortening an arrangement time without lowering accuracy in the instrumental error measurement of an electronic type water meter.

This electronic type water meter 11 has an ordinary operation display mode and an instrumental error measurement operation display mode having the 1/1,000 scale of an ordinary operation display, and when a reed switch 19 is switched on/off by an electromagnet 33, a display switching circuit 18 switches from the ordinary operation display to an instrumental error measurement operation display. When an instrumental error measurement start signal is output from an automatic verification device, the electronic type water meter starts metering, and after a prescribed water feeding quantity flows, a stop signal is output from the automatic verification device, and the electronic type water meter stops metering and displays a metered value in the instrumental error measurement operation display mode. Since the electronic type water meter has the instrumental error measurement operation display mode capable of displaying a smaller value than the ordinary operation display, the water meter can perform highly accurate instrumental error measurement with a small water feeding quantity without connecting a transmission line of the water meter to the automatic verification device, and thereby the arrangement time for the instrumental error measurement is saved and the work efficiency is improved.