The invention provides a real silk fabric printing and dyeing agent which comprises the following components: a maleic acid-acrylic copolymer, a dye, a softening agent, polyethylene glycol, an emulsifier, benzophenone, a color fixing agent, a defoaming agent, ethylene glycol and water. A preparation method comprises the following steps: firstly, mixing the dye, the softening agent, the polyethylene glycol, the emulsifier and the water, performing heating stirring, further adding the maleic acid-acrylic copolymer and the ethylene glycol, stirring, adding the color fixing agent and the defoaming agent, and stirring and mixing, thereby obtaining the real silk fabric printing and dyeing agent. With the combination of the maleic acid-acrylic copolymer, the polyethylene glycol and the benzophenone, the printing and dyeing agent is capable of improving the degumming efficiency of a real silk fabric when being printed and dyed, the printing and dyeing time is shortened, a relatively dark color and good color fastness can be achieved after the fabric is dyed, and the ultraviolet resistance of the fabric dyed with the agent is remarkably improved.