With the continuously increasing demands on imaging accuracy and on-orbit service life of space optical remote sensors, efficient thermal management under extreme thermal environments has become a critical bottleneck constraining their performance. The substantial temperature fluctuations induced by solar radiation and cold space can cause thermal deformation of optical components, elevation of focal-plane dark current, and even system failure. Traditional metallic thermal conductive materials can no longer meet the increasingly stringent requirements for heat dissipation and lightweighting. Carbon-based materials—including graphene, carbon nanotubes, and carbon/carbon composites—exhibit enormous potential for breaking through the bottlenecks of space thermal management by virtue of their ultra-high thermal conductivity, low density, and low coefficient of thermal expansion. However, systematic performance comparisons and application guidelines for these materials in the specific scenarios of space optical remote sensors remain absent, hindering the effective translation from laboratory research to engineering implementation. Therefore, a systematic review of the thermal conduction mechanisms, fabrication processes, and space applicability of carbon-based high-thermal-conductivity materials is of great significance for promoting their precise application in the thermal management of space optical remote sensors.