The invention relates to an experimental device for measuring a multi-dimensional spectrum, and particularly relates to an experimental device for measuring a photon echo spectrum. In order to solve the problems that an active phase stabilizing device is large in system, relatively high in cost and limited in application range in an existing two-dimensional electronic spectrum, and the problems that an existing passive phase stabilizing device is almost not high in detection accuracy of weak signals with relatively low signal light intensity and relatively difficult to control in polarization, the device provided by the invention comprises a femtosecond laser, an optical parametric amplifier, an attenuation slice, a reflection mirror, a polarizer, a beam splitting slice, a time delay device, a lens, a diffraction grating, a wedge-shaped prism pair, a parabolic mirror, a sample cell, a space diaphragm filter, a concave mirror, a polarization detector, a beam combiner, a spectrometer, a CCD array detector and a computer. The experimental device provided by the invention is applicable to the detection of the photon echo spectrum.