A method of manufacturing a hot press-formed part, in which the hot press-formed part is manufactured by hot pressing a surface-treated steel sheet (1) comprising a Zn-Ni plated layer formed on the surface of a base steel sheet, is provided with the following steps in order to suppress the generation of micro-cracks while suppressing deterioration in the shape-fixability during hot press-forming, namely: a step of heating the surface-treated steel sheet to a temperature in a range at least equal to the Ac3 transformation point and at most equal to 1000 DEG C; a step of cooling the surface-treated steel sheet at a cooling rate of at least 100 DEG C/s to a temperature at most equal to 550 DEG C and at least equal to 410 DEG C, by sandwiching the heated surface-treated steel sheet in a cooling die (3) of which the surface that is in contact with the surface-treated steel sheet is planar; a step of obtaining a formed body by starting to press-form the surface-treated steel sheet using a press-forming die (11) within 5 seconds after cooling, and while the temperature of the surface-treated steel sheet is in a range at most equal to 550 DEG C and at least equal to 400 DEG C; and a step of maintaining the formed body at bottom dead center of forming while the formed body is still sandwiched in the press-forming die, and quenching the formed body to yield the hot press-formed part.