Disclosed is an apparatus for measuring the strength of solar cells. The apparatus includes a shell, a flexible element, a fastener unit, an inlet valve and a vent valve. The shell is used to cover the solar cells. The flexible element is disposed in the shell, thus dividing the interior of the shell into a first chamber and a second chamber. The fastener unit is used to firmly attach the flexible element to the shell. The inlet valve is in communication with the first chamber. The vent valve is in communication with the first chamber.