The manufacture of carbonized La 2 O 3 -Mo cathodes for use in the 6T51tube,and their emission property were stu died.The study was based on current practice in the manufacturing of carbonized ThO 2 -W cathodes.Using similar techniqu es,carbonization of the La 2 O 3 -Mo cathode,evacuation of the carboniz ed La 2 O 3 -Mo cathode 6T51tube,and activatio n of the cathode were carried out.Mea surements taken on the6T51tube showed that the emission ab ility of the carbonized La 2 O 3 -Mo barely attained the lower limit o f clean W,let alone Th-W.Fur-thermore the emission is unstable an d the emission life can not be easily c ontrolled,possibly due to the consu mption of La and /or carbonized layer.