Cyanide-free gold electroplating liquid and gold plating method

The invention relates to the technical field of electroplating, in particular to cyanide-free gold electroplating liquid and a gold plating method. The cyanide-free gold electroplating liquid comprises gold sulfite, a complexing agent, an auxiliary complexing agent, a buffering agent, a crystallization adjusting agent and composite sulfonate. The complexing agent comprises one or more of sulfite and hydrosulfite; the content of the complexing agent in the cyanide-free gold electroplating solution is 10 g/L-50 g/L; the auxiliary complexing agent comprises one or more of sugar, sugar alcohol and sugar acid; the composite sulfonate comprises a first sulfonate and a second sulfonate, the first sulfonate comprises a compound with a structure as shown in a formula I, and the second sulfonate comprises a compound with a structure as shown in a formula II. The cyanide-free gold electroplating solution is good in stability in the storage period and the using process, and the service life of the electroplating solution