Provided is a handler apparatus that conveys a device under test to a test socket, including: a socket fitting unit which the test socket fits, prior to fitting of a device holder holding the device under test to the test socket; a test-socket position detecting section that detects a relative position of the socket fitting unit with respect to the test socket in a state in which the socket fitting unit fits the test socket; an actuator that adjusts a position of the device under test on the device holder, based on the detected relative position of the socket fitting unit; and a conveyer that conveys the device holder in which the position of the device under test has been adjusted, to fit the test socket.