The values of the phase integralqwere determined for asteroids using a numerical integration of the brightness phase functions over a wide phase-angle range and the relations betweenqand theGparameter of theHGfunction andqand theG₁,G₂parameters of theHG₁G₂function. The phase-integral values for asteroids of different geometric albedo range from 0.34 to 0.54 with an average value of 0.44. These values can be used for the determination of the Bond albedo of asteroids. Estimates for the phase-integral values using theG₁andG₂parameters are in very good agreement with the available observational data. We recommend using theHG₁G₂function for the determination of the phase integral. Comparison of the phase integrals of asteroids and planetary satellites shows that asteroids have systematically lower values ofq.