A protic ionic liquid (IL) [DBUH][Triz], prepared from 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,2,4-triazole (Triz), has been synthesized in this work. Then, the concentration-dependent electrical conductivity (κ) of binary solutions of [DBUH][Triz] with six molecular solvents, including four polar protic solvents (methanol, ethanol, isopropanol and n-butanol) and two dipolar aprotic solvents (dimethyl sulfoxide, DMSO and N,N-dimethylformamide, DMF), respectively, have been measured at temperatures ranging from 298.15 to 313.15 K. In addition, the electrical conductivities κ have been well correlated using the Castell–Amis equation with satisfying results. It has been found that within the solvent-rich range, the electrical conductivity κ first increased with increasing mole fraction of IL due to solvent–IL interactions. Afterwards, κ values of solutions gradually decreased due to the predomination of a strong electrostatic force between ions and enhancement of the viscosities of the solutions in the [DBUH][Triz]-rich region. Furthermore the maximum value of the electrical conductivity in [DBUH][Triz]/alcohol systems is in the following order: methanol > ethanol > isopropanol > n-butanol, which is consistent with the dielectric constants of the alcohols, indicating that an alcohol with higher dielectric constant can more readily promote the dissociation of [DBUH][Triz]. However, the electrical conductivity of the [DBUH][Triz]/DMF system is obviously larger than that of the [DBUH][Triz]/DMSO system although the dielectric constant of DMF is smaller than that of DMSO, implying that the viscosity could play the major role in determining the electrical conductivity of solutions of the IL with aprotic solvents.