Fused Deposition Modeling (FDM) is one of the prominent additive manufacturing technologies to fabricate a 3D physical part from a CAD model based on extrusion technique. However, the FDM-printed parts are produced by depositing melt filaments layer by layer and the mechanical properties depend on the interlayer bonding. This is because FDM 3D printing parts depend on the appropriate selection of parametric values to produce improved mechanical properties. This research focused on determining the better tensile properties of FDM 3D printing using PLA material with various combinations of process parameters such as extrusion temperature, print speed, raster width, shell number, and cooling fan speed. CFD analysis is used to measure temperature distribution at nozzle exit of deposited material for six different air forced cooling fan speeds having the maximum 6500RPM with 1300RPM decrement. It considered the steady-state, incompressible, and Newtonian fluid flow of air. On other hand, the parametric optimization of the FDM process is observed by Response Surface Methodology (RSM) techniques for better Tensile properties. The results show that the maximum drop in filament temperature for a given condition is about 22.85℃ as a result of forced convection of 6500RPM cooling fan speed. From the RSM analysis, the optimum parameter obtained is 79.298% of cooling fan speed, 214.3939℃ of extrusion temperature, 75.9091mm/s of print speed, 0.4814mm of raster width and 5 number of shells with only 2.266% percentage of error for 45.06MPa actual value. Finally, the SEM was conducted for morphological study of cooling fan speed with 0%, 50%, 80%, and 100% variations. Thus, the SEM image result shows PLA cooled with 80% seems to have good intra-layer bonding strength and elliptic deposited layer for which allows the surface contact in between inter-layer that reduces air void. Keywords: FDM; CFD analysis; Crystallinity temperature zone; RSM; SEM