Fuente: WIPO "tomato" The present invention provides a filling exhibiting a pattern which has at least two colors, is not fully mixed, and is irregular; a composite biscuit product comprising same; and a preparation method therefor. Using the present invention, it is possible to achieve an effect of a multi-colored irregular pattern when industrially producing composite biscuits (in particular sandwich biscuits). Viewed from a lateral side and a front side of the biscuit, the filling layer can be seen to exhibit the effect of a multi-colored pattern which has two or more colors, is not completely mixed, and is irregular.