The utility model discloses a side slope crackle width observation device, including scale rod and reading pole, scale rod comprises scale rule vertical upright rod and concrete foundation, and the scale is right angle rigid connection with scale vertical upright rod, and through firm the planting in the stratum on side slope crackle one side of concrete foundation, the scale is parallel with theside slope face, the reading pole is right angle rigid connection by reading chi, reading chi vertical upright rod, crackle width reading screw rod and concrete foundation, reading chi with reading chi vertical upright rod, and through firm the planting in the stratum of side slope crackle another side of concrete foundation, the reading chi is parallel with the side slope face, and crackle reading mark screw rod can freely slide on the reading chi, the utility model relates to a side slope crackle width observation device simple structure, convenient to use can accurately acquire crack borderwidth data, has improved the accuracy that fracture width surveyd greatly.