Based on the example of monitoring to the stability of the layered rocky high slope, base and foundation of the south tower of Jiangyin Bridge, the discipline of monitoring mesh design to its stability, the rational arrangement of monitoring spots, the embedding technology of hole with clinometer in fragmentary rock mass in high slope and the establishment of the monitoring and predictive model to the stability of high slope are elucidated. The discriminating discipline for the high slope stability based on the monitoring deformation result, and the quantitative evaluation method based on shear-slip, axial force and horizontal pushing force for the stability of high slope are suggested in the article.