This study explores the selective laser melting (SLM) of TC4 specimens, focusing on the comparison of variable layer thickness fabrication to fixed layer thickness specimens. The forming method of variable layer thickness fabricating was proposed and the superposition method of variable layer thickness was designed to explore the difference between the forming quality of variable layer thickness specimens and fixed layer thickness specimens. The research shows that the density of the specimen formed by 200 μm → 200 μm → 100 μm→ 100 μm→ 100 μm → 50 μm → 50 μm → 50 μm → 50 μm forming mode is higher than that of the specimen with 200μm layer thickness, reaching 99.13 %, and the building rate is 2.054 mm3/s, which is faster than that of the specimen with 100μm layer thickness. The surface roughness of this forming mode is 14.2μm, which is close to that of the 50μm thickness samples. The tensile strength of the variable thickness specimen can reach 1047.76 MPa, and the elongation can reach 6.18 %. The tensile fracture morphology of the variable thickness specimen is similar to that of the 50μm thickness specimen. Microstructure analysis revealed that the variable thickness specimens possess compact acicular martensite α′, and their tensile fracture morphology resembles that of the 50μm thickness specimen. The findings demonstrate the potential of variable thickness forming as a novel method in SLM formation, offering improvements in forming quality and rate under certain conditions, thus enabling the realization of high-quality and high-speed SLM-formed specimens.