The invention discloses a method for preparing a LiFePO4/SiC lithium battery positive plate by microwave heating. The method is characterized in that: the method comprises the following steps of 1, immersing LiFePO4 in a lithium silicate aqueous solution having mass concentration of 20 to 30% for 2 to 5 hours, fully stirring and evaporating water of the lithium silicate aqueous solution, 2, carrying out calcination of the immersed LiFePO4 at a temperature of 500 DEG C for 2 to 5 hours, 3, adding SiC having particle sizes of 100 to 150 microns into LiFePO4 powder obtained by calcination, wherein a use mount of SiC is 5 to 10wt% of that of LiFePO4, and carrying out uniform ball-milling mixing, 4, heating the mixture obtained by the step 3 in a microwave oven under the conditions of microwave power of 300 to 500W and heating time of 10 to 25 minutes, and 5, mixing the mixture obtained by the step 4, a binder, a conductive agent, an additive and a solvent into slurry, and carrying out coating, drying, rolling and cutting of the slurry to obtain the LiFePO4/SiC lithium battery positive plate. The method can effectively solve the problem of falling-off of LiFePO4 powder in coating and assembling and can obviously improve electrochemical performances of the LiFePO4/SiC lithium battery positive plate, and is simple in application and low in cost.