The present patent application relates to a process for dyeing keratin fibers, in particular human keratin fibers such as the hair, comprising a step of applying to said keratin fibers one or more 7-amino-1,2,3,4-tetrahydroquinoline derivatives substituted in position 8, to dye compositions comprising such 7-amino-1,2,3,4-tetrahydroquinolines, and also to the devices using these compounds.