In this paper, the structure, electronic energy band, and thermoelectric properties of bulk and monolayer fullerene (C₆₀) networks were analyzed in detail, stimulated by the successful experimental synthesis of C₆₀ networks [Hou L., et al., Synthesis of a monolayer fullerene network, Nature, 2022, 606, 507]. Our theoretical results for three-dimensional (3D) and 2D C₆₀ networks revealed the physical mechanism for the successful synthesis of a monolayer C₆₀ network. The calculated energy band, effective masses, Seebeck coefficient, and thermoelectric effect (ZT) of the C₆₀ network revealed that the C₆₀ networks have excellent thermoelectric properties. Also, the Dirac point can trap electrons for excellent thermoelectric properties. Different kinds of C₆₀ networks demonstrated superior Seebeck coefficients at low temperature and room temperature, respectively; which suggests they can be potentially applied in thermoelectric devices for working in different temperatures with high Seebeck coefficients. Our results can provide insights for understanding the origin of the thermoelectric properties of C₆₀ networks.