High quality epitaxial layers of nominally undoped ZnSe have been grown by metalorganic chemical vapor deposition at low temperature (325 °C) and pressure (30 Torr), using dimethylzinc and hydrogen selenide. All layers were unintentionally dopedntype with net carrier concentrations of 6.4×1014–1.5×1016cm−3and exhibited very high mobility at room temperature (up to 500 cm2/V s) as well as at 77 K, where the measured value of 9250 cm2/V s is the highest so far reported for vapor phase growth. Additional evidence for the high quality of the material is provided by photoluminescence. Experimental results indicate a correlation between the photoluminescence characteristics and the electrical properties that may be useful in assessing the quality of ZnSe films.