Creep-slide failure is a typical disease for excavated underground earthen sites in humid environment due to that most of the earthen sites are composed of fine clay particles with high moisture content and high plasticity, and exhibit creep-sliding failure character with the change of groundwater lever. In the study, the slender bamboo rod was employed for treating the creep-slide failure of the earthen sites in humid circumstances. A series of laboratory pullout tests were performed with the varied length of bamboo rod, the interface shear strengths were evaluated by comparing with the direct shear tests.