Abstract: An improved voltmeter of the liquid crystal display type comprising an electrically insulated casing 4, a detecting electrode 9 secured to its forward end, a liquid crystal display element 1 within the casing electrically connected to said detecting electrode, a grounded electrode 12 within the casing electrically connected to said display element, and a window 14 at the rear end of said casing for detecting the operation of said display element therethrough. The improvement consists in the further inclusion of a piezoelectric unit 2 and a pressurizing mechanism 3 in the casing 4. The normal operation of said liquid crystal display element can be confirmed through said window by applying to said liquid crystal display element a voltage which is produced in said piezoelectric unit when it is flexed by said pressurizing mechanism.