Abstract: On the basis of the analytical solution of axial energy propagation of transient electromagnetic pulse from an antenna unit, point source approximation model for transient electromagnetic pulses radiated from antenna array is introduced, and the physical mechanism of the effective energy density superposition is given. Arrayed transient electromagnetic pulse generator is used to prove the effective energy density superposition. Both of the experimental results and calculated results using point source approximation model confirm the effective energy density superposition of transient electromagnetic pulses from antenna array.