<p>The present work demonstrates the effect of different process parameters of the selective laser melting (SLM) process on the mechanical properties of 3D printed Ti6Al4V (Ti64) alloy. The design of experiments methodology was used to plan the experimental runs for preparing the specimens using various combinations of input parameters, viz., laser power, scanning speed, and layer thickness. The study employed the analysis of variance technique to determine the significant input parameters and their interactions with mechanical characteristics, viz., nanohardness and elastic modulus of the built specimens. For the selected ranges of input parameters, it was found that the laser power is the most significant parameter, as it contributes to 69.82% and 50.16% for nanohardness and elastic modulus, respectively. The increase in laser power results in the martensitic microstructure, which is compact, homogeneous, and highly dense, giving the maximum value of nanohardness and elastic modulus of the Ti64 alloys manufactured using the SLM process. The second significant process parameter is the interaction term combining layer thickness and scanning speed, with a contribution of 18.07% and 33.93% in nanohardness and elastic modulus, respectively. Further, the regression equations were developed and validated for predicting the elastic modulus and microhardness expressed as functions of laser power, scanning speed, and layer thickness for SLM manufactured Ti64 specimens.</p>