PURPOSE: To obtain a measuring device of compression of a housing lock lever which reduces a frictional force between the housing lock lever and a compression jig and reduces measuring error caused by the force.

CONSTITUTION: A roller-shaped contact fitting 19 is fitted rotatably to the fore end of a compression jig 18 and a connector 13 is disposed so that a housing lock lever 12 operates within a rotation surface of the contact fitting 19. When a head part 14 of the housing lock lever 12 is pressed by lowering the compression jig 18, the housing lock lever 12 is deflected with the head part 14 moved along a virtually circular-arc trace. On the occasion, the contact fitting 19 rolls on the head part 14 of the housing lock lever 12 and thereby a frictional force between the two parts 19 and 14 is prevented from being transmitted to the compression jig 19.