Melt pool shows inconsistency due to the varied heat conditions in selective laser melting (SLM) process, even if identical process parameters are used. The characterization of the actual melt pool shape is highly desired in order to eventually control the quality and property of additive manufacturing products. It has been well understood that base plate provides high thermal conduction while powder bed is low thermal condition for fusion energy to be dissipated. Based on former study of melt pool characterization on a base plate, this study creates single tracks on the support structure, which is considered the similar heat condition of the Ti-6Al-4V powder bed. Various patterns of the support structure are fabricated for single track deposition, in order to investigate the effect of the support structure on melt pool consistency and continuity. Different laser melting parameters are used in the experiments to understand their effects on the melt pool morphology.