Halogenated alkoxyphthalocyanine having a controlled grade of halogenation can be prepared by reacting a single compound or a mixture of phthalocyanine represented by the formula (1): ##STR1## wherein R.sup.1 is a substituted or unsubstituted alkyl group and may be the same or different, and Met is two hydrogen atoms, a divalent metal atom or a trivalent or tetravalent metal derivative, with 1 to 6 mole ratio of a halogenating agent at 0.degree. to 260.degree. C. in a solvent of from 1 to 1000 times by weight.