The invention provides a metal ceramic bonding agent diamond tool bit prepared by microwave sintering and a preparation method thereof. The diamond tool bit comprises the following substances of, by mass, 3 parts of diamond, 55 parts of electrolytic iron-copper-nickel-manganese alloy powder, 20 parts of copper powder, 10 parts of tin powder, 5 parts of zinc oxide and 12 parts of titanium dioxide.According to the diamond tool bit and the preparation method thereof, energy conservation and environmental protection can be realized, the working environment can be improved, and the labor intensityof workers can be reduced; due to the fact that holding force of a matrix to the diamond is enhanced, the service life and sharpness of the diamond tool bit are prolonged, so that electricity consumption of customers can be reduced in the product use process, more than 60% of electricity is saved compared with similar products, and production cost of the customers is reduced; according to a formula, the zinc oxide and the titanium dioxide inorganic substances are contained in a matrix, so that the red hardness of the diamond tool bit and the shape maintaining line of the product in the usingprocess are improved, and therefore the sharpness and the service life of the diamond tool bit are further enhanced, and the advantage of high cost performance of the product is achieved.