An efficient anchoring method, explicitly developed for small sliders, has hitherto been missing in the practice of earthen architecture conservation. Furthermore, anchorage performance studies conducted so far, have failed to fully take into account the soil characteristics of certain targets. To address these concerns, the conservation project conceived for the Gaochang Ruins, Turpan, in China, was selected as the experiment ground to design a novel Geotechnical Filament Anchor (GFA) for reinforcing small sliders in the earthen historical ramparts. In-situ experiments were conducted for evaluating six parameters—anchorage length (L), GF thickness (H), bore diameter (D), slurry strength (S), GFA surface status (R), and inclination angle (A). These parameters were varied in order to determine the effect they produce on anchorage performance, as demonstrated by the indicators, including tensile strength, destruction mode, load displacement (P-S) relation, and strain (ζ-L) distribution characteristics of the novel GFA. Data acquired from the experiments, in combination with the conservation specifics of earthen architectural sites, anchorage performance, and safety reserve, were further employed to introduce a calculation formula for computing the designed force value (N) through L. A simplified model depicting the shear stress distribution of the anchorage system under N was devised by extracting the strain distribution data with respect to the GF-slurry interface. Taking into account the soil properties of the above-mentioned site, the shear stress diffusion coefficient (α) was conceptualized, the formula for the shear strength of the grouting material was devised, and the tolerable ranges of L, D, H, R, and S were determined. A new design idea is proposed for the application of anchorage technology in earthen ruins in combination with the characteristics of cultural relics protection, which certainly promotes the formation of its design concept and calculation method.