The invention belongs to the technical field of rare earth indissolvable metal cathode materials, and relates to a preparation method of a pressing type scandium containing dispenser cathode based on microwave sintering. The preparation method comprises the steps that various kinds of nitrate and ammonium metatungsten are dissolved in plasma water to be prepared into an evenly-mixed solution, and precursor powder with even particles is obtained through spray drying; then the precursor powder is subjected to decomposition and secondary reduction to obtain doped tungsten powder with elements distributed evenly; and finally a microwave sintering method is used for preparing the cathode through one-time sintering. Sintering one-time forming of the cathode is finally achieved, the sintering shrinkage ratio is remarkably reduced, the sintering time is greatly shortened, the structure is uniform, repeatability is good, and excellent launching performance is achieved at the temperature being 950 DEG C.