Samples of Li_3-2xB_1-xN_xO₃(x=0.1,0.2,0.3)compound with pure phase were obtained by coprecipitation method at the first time.Lithium nitrate, lithium carbonate and boron oxide were as the raw materials.The Li_3-2xB_1-xN_xO₃(x=0.1,0.2,0.3)precursor powders were sintered via pressureless sintering.And Li_3-2xB_1-xN_xO₃(x=0.1,0.2,0.3)solid electrolytes were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The results show that samples Li_2.6B_0.8N_0.2O₃ sintered at 600℃ by the non pressure sintering showed the highest total conductivity of 6.37×10_-6S/cm.The activation energy is 0.48 eV at 250~390K. And its density is the reaching 90.07% of theoretical density.