An electron gun used with a multi-media monitor with a low cathode voltage and improved focusing performance. The electron gun, which includes a cathode, a control electrode, a screen electrode, and a plurality of focusing electrodes to focus and accelerate an electron beam, is designed to satisfy the condition that a value of .beta. is greater than or equal to 0.222 or a value of k is greater than or equal to 0.11, where .beta.=T1/D, k=T1/L, T1 denotes a thickness of the control electrode, D denotes a diameter of an electron beam aperture of the control electrode, and L denotes the distance between a beam-entering surface of the control electrode and a beam-emitting surface of the screen electrode.