Carbon nanotubes (CNTs) became a prominent material for its use in bioanalytical devices due to their biocompatibility, their particular structure, and their conductivity. CNTs have shown to be particularly appropriate to establish electronic communication with redox enzymes since the thin diameter can be approached closely to the redox active sites enabling therefore the regeneration of the biocatalysts either by direct electron transfer (DET) or with the help of so-called redox mediators which serve as intermediated for the electron transfer. The possibility to capture the enzymatic redox processes by obtaining catalytic currents, the use of such CNT-enzyme electrode for biological energy conversion represents the logic consequence. The development of CNT based enzyme biofuel cells (BFCs) is a still young but steadily growing research topic where original approaches to construct electron transfer based CNT-bioelectrodes and impressive biofuel cell performances are highlighted in this review. The evolution of reported biofuel cells consisting of CNTs and enzymes at the bioanode and the biocathode are summarized.