The invention discloses a railway member displacement monitoring system. The system comprises a digital image acquisition device, a server, a datum reference card and a displacement sign card, wherein the datum reference card is provided with at least four index points, a connecting line between any two index points among the four index points at least determines four non-superposed straight lines, the lens of the digital image acquisition device faces the datum reference card and the displacement sign card, and the signal output end of the digital image acquisition device is connected with the signal input end of the server. The railway member displacement monitoring system and method realize automatic calibration, measurement and storage, reduces the labor intensity, and at the same time, also eliminates interference of manual and environment factors.