A saccharide-assisted hydrothermal route starting from a single iron precursor was employed to study the influence of reducing saccharides on the formation of iron oxide (Fe3O4) nanoparticles (NPs). Fe3O4 NPs, which were confirmed by X-ray diffraction analysis, were successfully synthesized by a hydrothermal method in which mannose, maltose, lactose, and galactose served as reducing agents. The formation of Fe3O4 NPs was also confirmed by Fourier transform infrared spectroscopy. Samples exhibited different crystallite sizes estimated based on line profile fitting as 12 +/- 2, 9 +/- 2, 13 +/- 3, and 9 +/- 3 nm for mannose, maltose, lactose, and galactose, respectively. Magnetic characterization results revealed superparamagnetic features of the NPs obtained with galactose, mannose, and maltose.