Conjugated microporous polymers (CMPs) have emerged as highly versatile materials, garnering significant attention in recent years due to their unique structural and functional properties. This study presents the development and synthesis of a CMP based on Py-TBNBZ, achieved via a well-established [4 + 4] Schiff base reaction. The reaction involves two primary building blocks: 4,4′,4″,4‴-(pyrene-1,3,6,8-tetrayl)tetrabenzaldehyde (PyBZ-4CHO) and 4,4′,4″,4‴-(dibenzo[g,p]chrysene-2,7,10,15-tetrayl)tetraaniline (TBNBZ-4NH₂). The structural and morphological characteristics of the synthesized Py-TBNBZ CMP material were systematically analyzed using advanced experimental techniques, confirming the successful formation of a robust framework. The Py-TBNBZ CMP prepared in this study showed a BET surface area (S_BET) of 497 m² g⁻¹. Thermal analysis indicated a decomposition temperature (T_d10) of 476 °C and a notable char yield of 74 wt%, as confirmed through BET and TGA measurements. One of the most notable features of the Py-TBNBZ CMP is its strong fluorescence, which enabled its application in chemical sensing. The material exhibited exceptional sensitivity and selectivity, allowing for the detection of K⁺ and Fe²⁺ ions and precise pH monitoring over a broad pH range (pH 2–10). The underlying sensing mechanisms were investigated and elucidated. Additionally, the Py-TBNBZ CMP demonstrated remarkable adsorption capabilities for hazardous gas vapors, including ammonia (NH₃) and hydrogen chloride (HCl), underscoring its potential for environmental remediation. The flexibility of the Py-TBNBZ CMP distinguishes it from other CMPs and porous materials, enabling superior performance, enhanced applicability, and improved operational efficiency. This work highlights the advanced capabilities of Py-TBNBZ CMP and contributes to the ongoing development of innovative materials for adsorption, environmental protection, and next-generation sensing technologies.