An InGaAsN single-layer quantum dot (QD) laser structure was grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). The ridge-waveguide edge emitting laser diodes (LD) were fabricated and characterized. We demonstrate room-temperature operation of InGaAsN QD lasers with an emission wavelength of 1078 nm. Electroluminescence spectra as a function of injection current showed that InGaAsN QD LDs lased from an excited QD state at room temperature. The evidence for QD-related absorption was obtained from the comparison of photocurrent spectra between a reference InGaAs QW and the InGaAsN QD structures. (C) 2004 The Electrochemical Society.