The preparations of high-energy pentazolate salts is a research hotspot in the field of energetic materials. The preparation of pentazolate anion is a key step in the preparations of high-energy pentazolate salts. However， as the important precursors for pentazolate anion， the stability of existing arylpentazoles is generally not high. In order to develop new precursors of pentazolate anion with better properties， 18 substituted derivatives of PyN₅ with the electron-withdrawing and electron-donating groups， i.e.， R-PyN₅ （R=－NO₂， －CN， －NF₂， －OH， －OMe， －N（Me）₂）， were designed and studied by using the density functional theory method. The bond dissociation energy（E_BD）， and the activation energy（E_a1） of the bridged C—N bond and the activation energy（E_a2） of the cracking of the N₅ ring were calculated， and the stability of the bridged C—N bond and pentazolate ring were discussed. E_a1 of all molecules is smaller than E_BD， indicating that the breakage of the bridged C—N bond is more likely to follow the path 2 rather than path 1. E_a2 of all molecules is smaller than E_a1， indicating that the stability of the N₅ ring is the key factor to determine the stability of the arylpentazoles. Compared with PhN₅， —N（Me）₂ meta-substituted and bis-substituted compounds have lower E_a1， higher E_a2 and lower ΔE （E_a2－E_a1）. Therefore，—N（Me）₂ meta-substituted and bis-substituted compounds are the most potential precursors of N₅ˉ ion for replacing PhN₅.