This paper reports, the improved sensitivity and selectivity of liquefied petroleum gas (LPG) sensing at room temperature based on ternary heterostructure nanocomposite (CeO 2-rGO/CNT). Detection of LPG is required for proper environment monitoring to avoid any health hazards in the household and industrial areas. Towards this, a low-cost, high performance, and high stable room temperature gas sensor was fabricated. CeO 2 nanopuzzles was synthesized by Eggshell membrane template assisted hydrothermal method and nanocomposites by sono-chemical route. As-synthesized materials and nanocomposites were analyzed by employing characterizations like XRD, Raman, FT-IR, FESEM, and TEM, which confirmed the formation of shape, size, structure, and functional groups involved. The current study focuses on the fabrication of room temperature LPG sensor based on hybrid nanocomposites coated on flexible polyethylene terephthalate substrate working electrodes for In-house chemiresistive LPG detection unit to study response, stability, and selectivity parameters. The ternary heterostructure nanocomposite gas sensor exhibited good selectivity to LPG at room temperature. This sensor showed the response of 42% at 400 ppm of LPG, which is 2.21 times than pure CeO 2 sensor with a short response time 26 s and recovery time of 98 s, and gained 99% response after bending with 95.2% stability and 85.7% periodic stability of the sensor.