The invention discloses a low-permeability heavy oil reservoir vertical shaft thermal recovery pressure distribution prediction method and system. The method comprises the following steps of building a variable-starting-pressure gradient model, building a low-permeability heavy oil reservoir variable-starting-pressure gradient model according to the temperature distribution in different positions at the shaft bottom of a vertical shaft, building a seepage flow model, zoning a vertical shaft thermal recovery seepage flow field according to the variable-starting-pressure gradient distribution features so as to build a seepage flow equation corresponding to each zone, building a pressure distribution prediction model, and solving the seepage flow equation of each zone according to the variable-starting-pressure gradient model so as to obtain the pressure distribution prediction model of each zone. The theoretical basis is provided for optimizing the reasonable development mode and the well-net and distance.