Provided is a measurement socket with which an electronic optical part can be accurately positioned, and with which reliable conduction and optical axis alignment can be carried out. A measurement socket according to one embodiment of the present invention measures an electronic optical part and comprises: a base having a recessed part in which the electronic optical part is accommodated; a cover that covers the base; a pressing member for pressing the electronic optical part against a reference wall; and a timing adjustment member that adjusts the timing at which an operation of the pressing member is initiated. In a state in which the electronic optical part is accommodated in the recessed part, the pressing member is pressed by the timing adjustment member on the basis of an operation in which the cover is closed, and the electronic optical part is thus pressed against the reference wall. Therefore, the electronic optical part can be accurately positioned, and reliable conduction and optical axis alignment can be carried out.