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To ensure the robust design freedom of metallic additive manufacturing, the fatigue properties and the dimensional limitation of as-built components by laser powder bed fusion (PBF-LB) are investigated. Fully reversed and strain-controlled fatigue tests were carried out on tubular specimens with different wall thicknesses, 1mm and 2mm, for the purpose of studying the thin-wall effect without having risk of buckling problem during compression. Two wrought conditions are also enclosed as a comparison, which are the cold worked (CW) and solution annealed condition (SA). In the as-built PBF-LB tubular specimens, deformed microstructure and deformation twins are discovered close to the surface region, together with a higher roughness of the inner surface due to the heat accumulation. The surface roughness is evaluated as micro-notches, and a higher fatigue notch factor, K_f, at lower applied strain range is …