A thin film transistor array panel includes a first substrate; a gate line and a data line on the first substrate; a storage electrode line on the first substrate where a constant voltage is applied thereto; a first thin film transistor and a second thin film transistor which are connected to the gate line and the data line; a third thin film transistor which is connected to the gate line, the second thin film transistor and the storage electrode line; a first subpixel electrode which is connected to the first thin film transistor; and a second subpixel electrode which is connected to the second thin film transistor.