A toner for developing latent electrostatic images including a coloring agent, and a binder resin composition having resin particles, each resin particle having a matrix and domain particles with an average particle diameter of 0.5 to 2.0 .mu.m dispersed in the matrix; with the toner having such rheological characteristics that the storage elastic modulus (G') thereof at 80.degree. to 100.degree. C. under a frequency of 100 Hz is in the range of 5.times.10.sup.6 to 5.times.10.sup.7 dyne/cm.sup.2, and the loss elastic modulus (G") thereof at 200.degree. to 220.degree. C. under a frequency of 100 Hz is in the range of 1.times.10.sup.3 to 1.times.10.sup.5 dyne/cm.sup.2.