As an external physical factor, electromagnetic field (EMF) may influence cellular processes and nitric oxide (NO) by serving as a secondary messenger molecule in intracellular signaling cascades. Effects of these factors were evaluated simultaneously on viability, morphology, and variation of calcium ion content, and neural protein marker expression in rat bone marrow mesenchymal stem cells (BMSCs). The mesenchymal stem cells were isolated from rat bone marrow and cultured. Deta-NO as a donor molecule of NO was added to cell culture medium after several passages. These cells were also exposed by retinoic acid (RA, a molecule inducing cell differentiation) and EMF (50 Hz and 20 mT). Despite the effect observed with low concentration of NO, the high concentration of NO in the presence of EMF decreased cell viability and changed cell morphology. EMF increased entry of calcium ion into the cell. Effect of RA on cell death and morphology changes also intensified in the presence of NO and EMF. BMSCs maintained their proliferative state and continued to remain as a stem cell in low concentration of NO. The decrease of cell viability, and increase in number and length of cell neurites and percentage of cells expressing Map2 marker can be a sign of progression for cell neuronal differentiation treated by high concentration of NO with EMF. Bioelectromagnetics.