PURPOSE: To simultaneously carry out heat treatment required after coloring with that of a ground fish meat raw material itself and contrive improvement in processing capacity and reduction of equipment cost, by coloring the surface of a fish-paste product before completing heat treatment of the ground fish meat raw material constituting base meat.

CONSTITUTION: The surface of a fish-paste product is colored before completing heat treatment of a ground fish meat raw material constituting beam meat. Specifically, e.g. methods for extruding a ground fish meat raw material (a2) constituting a surface colored layer on the surface of the white ground fish meat raw material (a1) for base meat in an integrated state using a surface coloring device (B) built in a forming nozzle 4 of a continuous apparatus for preparing a beltlike fish-paste product and the heating the resultant extruded integrated fish meat raw materials, are cited.