Covalent Organic Frameworks (COFs) with unique π-structures and exceptional stability are promising candidates for photocatalytic CO2 conversion. However, most reported COFs exhibit significant recombination of photo-generated charges and holes, along with low CO2 chemisorption, leading to suboptimal photocatalytic performance. Here, we designed covalently linked two-dimensional cobalt (II) porphyrin layers and introduced various tetra-alkylammonium cations (─CH2N+(CH3)3, ─CH2CH2N+(CH3)3, or ─CH2CH2CH2N+(CH3)3). The tetra-alkylammonium cations within the ionic covalent organic framework (iCOF) stabilize the intermediates of the photoreduction reaction and accelerate the reaction kinetics through electrostatic field interactions, thereby facilitating the conversion of *CO2 to *CO. Molecular dynamics simulations further indicate that tetra-alkylammonium side chains increase CO2 residence time in the pores, thereby enhancing interaction with catalytically active sites. Furthermore, the electrostatic field effects of the tetra-alkylammonium cations increase the charge density at the Co center, stabilize CO2 reaction intermediates, and facilitate proton transfer. Remarkably, these advantageous effects synergistically contribute to the photocatalytic CO2-to-CO conversion. The CoTph-3C-N+ COF achieves an impressive CO initial production rate of 1006 mmol gCo−1 h−1 and a quantum efficiency of 5.67% at 420 nm, which is 17 times that of the pristine COF. This strategy offers a novel approach to designing various photocatalytic systems aimed at efficient chemical transformations.