The present invention provides a toner for developing electrostatic latent images, including resin particles containing a crystalline polymer and an amorphous polymer, wherein the amorphous polymer and the crystalline polymer satisfy the relationship represented by the following formula (1), and a method for manufacturing the toner of the invention. The present invention also provides a developer for electrostatic latent images including the toner of the invention and a carrier; and an image forming method using the toner of the invention. Further the invention provides a method for manufacturing a dispersion of resin particles. .delta.a-.delta.c.gtoreq.1.05[(cal/ml).sup.1/2(25.degree. C.)] Formula (1)In formula (1), .delta.a represents a solubility parameter of the amorphous polymer, and .delta.c represents a solubility parameter of the crystalline polymer.