Abstract Semiconducting nanocrystalline thin films of magnesium selenide have been prepared using economic chemical bath deposition technique onto glass substrates at room temperature. The deposition bath consists of magnesium chloride, triethanolamine, hydrazine hydrate and selenium dioxide. The quantity of triethanolamine in the deposition bath was varied to study its effect on growth process as well as on physical properties of MgSe. The deposited films were characterized using X-ray diffraction, scanning electron microscopy and atomic force microscopy techniques. The effect of complexing agent (TEA) on optical and electrical properties is reported. It was found that as the triethanolamine in deposition bath increases, optical band-gap and electrical resistivity decreases. The thermo-emf measurement shows p-type nature of MgSe.