Provided is a collected current monitoring device enabling an analysis of collected current in each current collector while allowing a reduced equipment cost. The collected current monitoring device of the present disclosure is installed in a railroad vehicle including current collectors, main transformers, and main converters. The collected current monitoring device includes: a supply current sensor configured to measure a current supplied to a freely-selected one of the main transformers, at least one current-sensor-between-current-collectors disposed in each communication path connecting two adjacent ones of the current collectors and configured to measure a current flowing in the communication path, and a processor configured to calculate a current flowing in each of the current collectors based on the current measured by the supply current sensor and the current measured by the at least one current-sensor-between-current-collectors, and on a distribution ratio of the currents supplied to the main transformers.