A seat molded article and a method of preparing a seat molded article are disclosed. The seat molded article includes: an upper pad formed of polyurethane foam having a thickness in a range of 25 to 50 mm; and an elastic fabric disposed under the upper pad, wherein, in the elastic fabric, a difference in tensile elongation between warp and weft directions is 5.0% or less, and a tensile elongation measured under a load of 20 kgf is in a range of 20 to 40% in the warp and weft directions.