Summary Phase change materials (PCMs) can optimize the thermal properties of fabric. Twelve kinds of microencapsulated phase change materials were selected, including four different phase change temperatures and three different content gradients. Twelve kinds of PCM‐coated fabrics were prepared by dry coating, and their basic physical properties were tested. The PCM‐coated fabric was added to the thermal protective fabric system as a comfortable layer. The thermal protective performance of the fabric system under two conditions of low‐level thermal radiation and fire exposure was analyzed through second‐degree burn time. The results showed that the incorporation of PCMs greatly improved the thermal protective performance of the fabric system under the low‐level thermal radiation, which was affected by the content, phase change temperature, mass per unit area and thermophysical properties of the coated fabric. In addition, the coated fabric by the PCMs was proved to be suitable for the condition of fire exposure, and greatly increased the thermal protective performance of the fabric system. The coated fabric with phase change temperature of 35°C and content of 45% showed the best thermal protective performance under both low‐level thermal radiation and fire exposure conditions.