The economic and scientific interest in Hancornia speciosa Gomes (mangabeira) has increased in recent years, especially due to the commercialization of its fruits and the extraction of natural compounds with high pharmacological potential. This paper aims to determine and correlate the main physical and biometric characteristics of fruits and seeds of mangaba tree, as well as identifying the most appropriate substrate for the seedling emergence test. The following physical and biometric traits were measured in 100 fruits and 100 seeds: longitudinal diameter, transverse diameter, thickness, fresh mass, pulp fresh mass, volume, number of seeds. To identify the best substrate, a completely randomized design with two treatments (substrates) and ten replications of 20 seeds was used. The evaluated substrates were: sand and commercial substrate (Plantmax HT®). The shoot height, root length, stem diameter, total dry mass, and the relation between shoot height and stem diameter were evaluated at 50 days after sowing. Mangaba fruits and seeds showed great variations in their biometric traits, in addition to significant and positive correlation predominant in most characteristics. High fruit pulp yield can be optimized with the selection of plants with fruits show greater fresh mass due to the high degree of association between this characteristic and pulp yield. The use of the commercial substrate resulted in higher shoot height, greater number of leaves, and higher shoot height/stem diameter ratio.