Abstract: 75 mg (NH₄)₆Mo₇O₂₄ •4H₂O solution was irradiated for 20 min in miniature neutron source reactor (MNSR) and cooled for 12 min. In the conditions of 0.8 mol/L HNO₃, phase ratio 1∶1, the solution of ¹⁰¹Tc sample was extracted twice with α-benzoin oxime/ethyl acetate phase to remove ¹⁰¹Mo and a radiochemically pure and carrier-free ¹⁰¹Tc product was obtained. The half-life of ¹⁰¹Tc was accurately measured with a HPGe γ-detector by following 306.8 keV γ-ray about 150 min, and processed the data by three methods, R-value method, iterative method and translation method. Five parallel measurments gave a half-life (14.02± 0.01) min （n=5） for ¹⁰¹Tc.