To provide a resin composition having a good slightly bluish color tone, a spectacle lens including a base material made of the resin composition, and a method for producing the resin composition.Provided is a resin composition obtained by polymerizing a polymerizable composition including a polyisocyanate compound and a polythiol compound. The polymerizable composition includes a dye L having an absorption maximum wavelength of 550 nm or more and 600 nm or less in a toluene solution of 20 ppm by mass, and a dye S having an absorption maximum wavelength of 500 nm or more and less than 550 nm in a toluene solution of 20 ppm by mass. A mass ratio [(mass of dye L)/(mass of dye S)] of the dye L to the dye S is 5 or more and 500 or less.