An oven gasket is provided for improved sealing between the door and oven body of an oven appliance as the oven is heated. The oven gasket expands when heated so as to help improve sealing. The expansion of the gasket provides additional compression of the gasket and closes gaps that might otherwise form due to expansion of the oven door as the oven heats. The gasket can be effective even at high temperature oven operation such as e.g., during a cleaning cycle.