Abstract: After the determination for lithium isotope abundant was accomplished, the electrical current on the ionization and vaporization strip is increased and the big current of lithium ion is kept. The ionic current of Li2 is inspected by magnetic field scanning and the ionic current of Li₂ is reality, but ¹²Li₂^＋、¹³Li₂^＋、14Li₂^＋ are not separated and they compose the widest peak form.