Determination of some seed characteristics provides important distinctive taxonomic data for species identification. In this study, seed characteristics such as measurements, weights and surface morphology of some unstudied taxa belonging to Fabaceae, Polygonaceae, Primulaceae, Violaceae, Rosaceae and Phyllanthaceae families native in Turkey, were investigated. Length and width of the seeds were measured with digital calliper using stereo-microscope. Seed weights were measured with Dikomsan precision scale. In addition to stereo microscope data, the surface ornamentation of the seeds was identified using scanning electron microscope. Accordingly, the smallest seeds were determined in Anagallis foemina (0.74 mm long and 1.11 mm wide) from Primulaceae family, while the largest seeds were determined in Rosa boissieri (4.95 mm long and 2.99 mm wide) from Rosaceae family. The heaviest seeds were measured in Rosa boissieri (0.0095 g) from the Rosaceae family and the slightest seeds in Anagallis foemina (0.0002 g) from the Primulaceae family. Mainly six types of the ornamentation were observed in SEM study of the species. The most common one was the reticulate ornamentation.