MDO may refer to:
Marine diesel oil, a type of distillate diesel oil MDO (band), a Latin American pop/rock band from Puerto Rico Medium density overlay, a type of plywood Mixed-domain oscilloscope, a type of oscilloscope used for FFT-based spectrum analyzer functionality Multidisciplinary design optimization, in engineering Multi-Domain Operations, the United States Army's central concept of operations Music Development Office, a music organisation in South Australia