In this research, the application of BN, BP, AlN, and AlP edge-doped graphene nanoflakes as sensor for sensing of H₂ molecule was studied by DFT approach. The M06-2X/6-311G++(d,p) level of theory have been used in the calculations. The results showed that the adsorption of H₂ molecule on the BN, BP, and AlN was very weak (−0.97, −0.16, and −1.14 kcal.mol⁻¹, respectively). By considering the acceptable adsorption of H₂ molecule on the AlP-doped graphene with −5.03 kcal.mol⁻¹, further calculations were performed on this sheet. Upon adsorption of H₂ molecule, the HOMO–LUMO gap (E_g) of the AlP-doped graphene nanoflake decreased slightly from 2.01 to 1.92 eV. Therefore, the electrical conductivity of AlP-doped graphene sheet increased. Moreover, ΔH_ad = −3.38 kcal.mol⁻¹ and ΔG_ad = −1.38 kcal.mol⁻¹ show that the adsorption of H₂ molecule on the AlP-doped graphene is an exothermic and spontaneous phenomenon at room temperature. The NCI-RDG analyses verifies the presence of vdW interactions between H₂ molecule and the AlP-doped graphene. Finally, according to the very low recovery time as 4.65 ns, AlP-doped graphene might be utilized as an effective and fast sensor for H₂ molecule at room temperature.