To provide a method for manufacturing pigmentary 1,4-diketopyrrolo[3,4-c]pyrrole directly, that is, without additional after-treatment for reducing a particle size of the pyrrole.

A direct manufacturing method of the pigmentary 1,4-diketopyrrolo[3,4-c]pyrrole expressed by formula (I), wherein, each of R1 and R2 is a carbon ring or a heterocyclic aromatic independently, includes a step of preparing a compound of the formula (I) by heating an appropriate mole ratio of disuccinate with a nitrile of formula (II): R1-CN or formula (III): R2-CN or with a mixture of the nitriles in an organic solvent and in the presence of a strong base and an effective amount of a particle growth inhibitor and then from a reaction product by protolysis.