In this paper, a multi-material non-assemble 3-DOF Force-Sensor was proposed and developed to improve the efficiency in the manufacturing. The PLA-Filament was used to produce the frame-structure and the elastic-deformation, and the conductive-PLA-filament, to produce a transducer. A dual-nozzle 3D-Printer was applied to produce the monolithic-structuretype force-sensor with the multi-materials simultaneously in single-manufacturing-process. The sensor was designed in a tripod-structure to detect the 3-DOF force-components in an external-force and a mechanical-interpretation was conducted on the elastic-deformation, which acts as a load-cell. The output model of a Wheatstone-bridge circuit-based transducer serving as a strain-gauge was also produced. A calibration-testing device, comprising a rotating stage, which turns with 2- DOF (θ, ϕ), was also developed to apply force in every direction. By conducting the calibration test, the relations between the input and output were computed in as a matrix and the resolution of the sensor was determined through the evaluation of linearity and stability deviations.