In this study the atomic layer deposition (ALD) of TiO₂ and ZrO₂ using two heteroleptic amido-guanidinate precursors, [Ti(NEtMe)₃(guan-NEtMe)] and [Zr(NEtMe)₃(guan-NEtMe)], together with water or ozone as oxygen sources, are investigated. All processes exhibit self-limiting growth at a deposition temperature of 275°C. The zirconium precursor especially gives high growth rates (0.8/1.0Å per cycle with H₂O/O₃). The films are also relatively smooth, as determined by atomic force microscopy (AFM). The composition of the films is examined using X-ray photoelectron spectroscopy (XPS) and time of flight elastic recoil detection analysis (TOF-ERDA). When using ozone as the oxygen source the films present very high purity. The results are compared and discussed with respect to earlier studies on guanidinate, as well as homoleptic amido precursors.