Disclosed is a contact-pressure adjusting method and a contact-pressure adjusting system, each of which automatically adjusts the contact pressure between two rotors, for a liquid application machine including: a first rotor to which liquid is supplied; a second rotor to which the liquid is supplied from the first rotor; and a contact-pressure adjusting unit for adjusting the contact pressure between the first rotor and the second rotor. By using a temperature measuring unit, measured is: the temperature of at least one of the surfaces of the first and second rotors; the temperature of at least one of the liquid on the surface of the first rotor and the liquid on the surface of the second rotor; or the temperature of at least one of the vicinity of the first rotor and the vicinity of the second rotor. The contact-pressure adjusting unit is adjusted in accordance with the measured temperature.