The invention relates to a
dyeing process for
collagen fiber regenerated leather. The process successively comprises at least two
dyeing treatment, at least one fixation treatment, at least one handfeel modification and
drying treatment, wherein
dyeing, fixation and handfeel modification are all carried out in an supersonic
sound field, so a coloring agent, a fixing agent and a handfeel modifier can effectively penetrate into
collagen fiber bundles so as to obtain a more uniform dyeing effect. The concentration of the coloring agent in sequentially used bath liquids increasingly decreases, temperatures of the bath liquids gradually increase, the power of the supersonic
sound field increasingly decreases, so bath liquids with
high concentration can infiltrate into a leather blank at first, and flooding which is serious in the process of
filtration can be eliminated in subsequent dipping in liquids with low concentration; thus, flooding generated in subsequent procedures increasingly decreases, and uniform dyeing of the leather blank is realized. Moreover, surface flooding is eliminated in virtue of a
brush of a
brush roller in the invention. The invention also relates to a dyeing apparatus capable of realizing continuous uniform dyeing of cloth and leather.