A connector connection structure includes: a case having a side surface and a top surface, respectively extending in directions crossing each other at a first angle, and an opening; a connector terminal portion inserted into the case from the opening; a shield plate closing the opening; a bolt fastening the case and the shield plate; and a terminal block arranged in the case and connected to the connector terminal portion. The shield plate has a first portion extending along the side surface and closing the opening, a second portion extending along the top surface, and a bent portion positioned between the first portion and the second portion and bent at a second angle being smaller than the first angle. The bolt fastens the case and the second portion of the shield plate.