Electromagnetic pulse emission of Shenguang-III prototype laser facilities from pulse-laser-irradiated metallic target is evaluated by using B-dot. An electric signal lasting for about 60 ns is detected in the experiment, with radiated field up to 3 kV/m and frequency bins for 0.1 GHz-2 GHz which has an obvious peak at 160 MHz. The results demonstrate that the model of dipole radiation is one of the major mechanisms of electromagnetic pulse emission from laser-target interaction. The dipole radiation model can produce about 105 W, 160 MHz central frequency electromagnetic pulse with an energy conversion efficiency of 10-6 according to the calculation, and the electric field of antenna position is about 2 kV/m. This experiment evaluates the electromagnetic pulse emission from pulse-laser-irradiated metallic target on Shenguang-III prototype laser facilities, which is of great significance for shielding electromagnetic disturbance of diagnostics on large laser facilities. Moreover, investigation of eletromagnetic pulse emission may have many potential applications.