An apparatus for supporting setting of a manufacturing condition of a vitreous silica crucible includes: an improved property parameter setting unit configured to, if the degree of matching between three-dimensional shapes of simulation data obtained based on an initial property parameter and measurement data falls below a predetermined level, set an improved property parameter such that the degree of matching becomes higher than or equal to the predetermined level, and an improved manufacturing condition data setting unit configured to set a manufacturing condition such that simulation data matching the design data to a degree higher than or equal to a predetermined level is obtained. By using the apparatus, it is possible to manufacture a vitreous silica crucible by rotational molding in such a manner that the three-dimensional shape thereof matches the design data to a high degree.