An electronic device includes a circuit board, a socket on the circuit board and electrically connected to the circuit board, and a tray removably insertable into the socket from outside the electronic device, the tray including a body portion, a first protrusion extended from the body portion, and a second protrusion extended from the body and spaced apart from the first protrusion. The socket includes a detection portion which is engageable with the first protrusion of the tray and detects insertion of the tray in the socket, together with the circuit board, and a supporting portion which is engageable with the second protrusion of the tray. The tray which is inserted into the socket disposes the first protrusion contacting the detection portion, and a portion of the tray corresponding to the second protrusion supported by the supporting portion.