A method for producing a foamed molded product includes: using a molding apparatus including a plasticizing cylinder having a high pressure kneading zone and a pressure reduction zone; and a screw; controlling a pressure of the pressure reduction zone to be a first pressure in a state that communication between the high pressure kneading zone and the pressure reduction zone is shut off, the first pressure being not less than an atmospheric pressure and not more than a maximum pressure of the high pressure kneading zone which is reached in a case that a molten resin is brought in contact and kneaded with a physical foaming agent; controlling back pressure of the screw to be a second pressure which is not less than the first pressure; and measuring a predetermined amount of the molten resin from which the gasified physical foaming agent has been separated.