With growing production and application, the presence of carbon nanomaterials (CNMs) in soil contaminated by organic pollutants (OPs) is inevitable and widespread because of their unintentional discharges. The strong sorption of OPs by CNMs can alter the bioavailability to microorganisms, which is important for their biodegradation. Meanwhile, the potential ecotoxicity of CNMs to soil microorganisms can also significantly affect biodegradation and bioremediation of OPs. To date, most studies have mainly focused on the impact of CNMs on the microbial availability of OPs and their degradation; the knowledge regarding the microbial response to CNMs and its impact on the biodegradation of OPs and the associated physiological mechanisms is very limited. This paper presents an overview on how CNMs may affect the microbial degradation of OPs (in soil) based on the effects of OP–CNM interactions on the microbial availability of OPs and those of CNMs on the activity and degradation capability of microorganisms at both cellular and community levels. Furthermore, that the ubiquitous dissolved organic matter (DOM) may influence the sorption and immobilization of OPs by CNMs and ecotoxicity of CNMs and the associated impacts on the biodegradation of OPs in addition to the underlying mechanisms regulating these processes are also investigated.