In this work, solution-processing rubrene spherulites were fabricated by blending an amount of polymer into rubrene and subsequent solvent vapor annealing (SVA). The content and molecular weight of the blended polymer, the annealing solvent and the solvent vapor pressure have tremendous influence on the formation of rubrene spherulites. Rubrene spherulites were produced only when a polymer with a high molecular weight was blended and annealed by good solvents of rubrene with high vapor pressures, such as CH₂Cl₂ and CS₂. The sizes of the spherulites decreased with the reduction of the annealing solvent vapor pressure. The rubrene spherulites adopted a triclinic system with c-axis perpendicular to the substrate. The crystallizing kinetics study displayed a rather fast growth of rubrene spherulites and the crystallization of rubrene was controlled by diffusion. A competitive mechanism between the impetus of the annealing solvent vapor and the impeditive force of the polymer on the diffusion of rubrene molecules to the crystal fronts was proposed to explain the formation of rubrene spherulites.