Body temperature is an important indicator of the health status of the human body. Thus, numerous studies have been conducted in various fields to measure body temperature. In this study, a biocompatible thermochromic membrane that changes its color when the temperature becomes higher than the transition temperature for thermochromism was fabricated using an extrusion-based three-dimensional printing process. The printing material was prepared by mixing a thermochromic pigment and a thermoplastic polymer in various ratios. The effects of mixing ratio on the various properties of the fabricated membranes were experimentally investigated. It is presented that the fabricated lattice membrane had excellent thermochromic reaction, which was experimentally evaluated using a measurement of color brightness. The pigment content affected the diameter and surface morphology of the printed filament. The elastic modulus decreased, and thermochromic response became faster as the pigment concentration increased. Subsequently, a patch for fever detection was developed and then attached to the skin to demonstrate its color change according to body temperature. Results show that the fabricated thermochromic patch could be successfully applied to fever detection.