NOVELTY - Producing a gallium phthalocyanine crystal, comprises subjecting a gallium phthalocyanine and an amine compound (I), which are added to a solvent, to a milling treatment to perform crystal transformation of the gallium phthalocyanine.    USE - The method is useful for producing a gallium phthalocyanine crystal comprising the hydroxygallium phthalocyanine crystal, which is useful for producing an electrophotographic photosensitive member including a support and a photosensitive layer formed on the support (all claimed), as a photoconductor, and in a solar cell, a sensor and a switching element. The electrophotographic photosensitive member is useful in electrophotography such as a laser beam printer, a calibrating monitor (CRT) printer, an light emitting diode printer, a short for facsimile (FAX), a liquid crystal printer, or laser plate making.    ADVANTAGE - The method provides: gallium phthalocyanine crystal having excellent characteristics as a charge-generating substance; and electrophotographic photosensitive member with improved sensitivity and capable of outputting an image having less image defects due to a ghost phenomenon not only under a normal-temperature, normal-humidity environment under a low-temperature, low-humidity environment as a particularly severe condition.    DETAILED DESCRIPTION - Producing a gallium phthalocyanine crystal, comprises subjecting a gallium phthalocyanine and an amine compound of formula (I), which are added to a solvent, to a milling treatment to perform crystal transformation of the gallium phthalocyanine.    R1-R10 = acyl, alkyl, alkoxy, aryloxy, cyclic amino group (all optionally substituted), H, halo, aryloxycarbonyl or an amino group having a substituent, where at least one of R1-R10 is optionally substituted cyclic amino group or amino group substituted with optionally substituted aryl or optionally substituted alkyl group, the amino group substituted with the alkyl group (optionally substituted) comprises a dialkylamino group comprising one of a dimethylamino group and a diethylamino group, and the cyclic amino group comprises one of a morpholino group and a 1-piperidino group; and    X1 = carbonyl or dicarbonyl.    An INDEPENDENT CLAIM is included for producing an electrophotographic photosensitive member (1) including a support and a photosensitive layer formed on the support, where the photosensitive layer contains the gallium phthalocyanine crystal, comprising producing the photosensitive layer with the gallium phthalocyanine crystal obtained by the above method.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of an electrophotographic apparatus provided with a process cartridge having the electrophotographic photosensitive member.    Electrophotographic photosensitive member (1)    Axis (2)    Charging unit (3)    Image exposure light (4)    Developing unit. (5)