To provide an apparatus for controlling an electric rolling stock, which shortens a wiring provided between an electric motor and an electric power converter and acting as a noise source, can take a comparatively fresh external air into a cooling fin of the electric power converter, and achieves space savings, miniaturization and weight reduction.

The apparatus for controlling an electric rolling stock includes: the electric power converter in which a gate amplifier, a filter capacitor and a semiconductor element are arranged in this order in the direction from a vehicle floor face to a bogie; a heat radiation fin provided in a side surface on the bogie side of the semiconductor element; the electric motor connected to the bogie and driven by the AC power converted by the electric power converter; and a cooling air duct provided with the heat radiation fin and communicating a cooling air inflow vent of the electric motor with an external air vent connecting to the external air. The electric power converter and the cooling air duct are installed below the floor in the proximity of the bogie.