The thermal insulation performance of flexible composite pipes under complex operating conditions has become a critical constraint on efficient oil and gas transportation, as these pipes are widely used in oilfield gathering systems. Aerogel, a novel insulating material with low thermal conductivity, lightweight, high porosity, and large specific surface area, shows significant potential to enhance the thermal insulation of flexible composite pipes in energy-saving oilfield applications. In this work, aerogel insulation layers with thicknesses of 0, 1.5, 3, and 4.2 mm were integrated into DN80mm PN6.4MPa flexible composite pipes to investigate their pressure resistance and thermal insulation properties. The results showed that the burst pressure of the pipes gradually decreased with increasing aerogel thickness, with an 8.64% reduction observed for the 4.2 mm group compared to the blank group. However, stable pressure retention confirmed that the aerogel layer did not compromise the fundamental pressure-bearing safety of the pipes. Concurrently, the thermal conductivity of the pipes significantly decreased, achieving a maximum reduction of 69.29% with thicker aerogel layers. Under the premise of ensuring safe pressure resistance, optimizing the thickness of the aerogel insulation layer effectively reduces thermal conductivity and enhances thermal resistance, providing robust technical support for cost reduction and efficiency improvement in oilfield gathering systems.