In this study, Group IIA element ion-doped g-C3N4 samples were synthesized to eliminate above two disadvantages and increase photocatalytic NO removal activity. The experimental results showed that the Group IIA element ions could form coordination bonds with the nitrogen atoms in the triazine rings of g-C3N4 that distorted the g-C3N4 structure because of uneven force. The structure distortion destroyed the surface electronic delocalization and suppressed the recombination of surface charge carriers. Additionally, the formed coordinate bonds connected two adjacent layers and served as interlayer electron channels, which could significantly improve the electron transport between two layers. Additionally, structural distortions created more amino and imino groups, which are the chemisorption sites of O2. Therefore, the modified g-C3N4 samples produced more reactive oxygen species to remove NO. The degree of distortion and the NO removal activity increased as the Group IIA atomic number increased.