Communist Workers Organisation (in Dutch: Kommunistische Arbeidersorganisatie (marxistisch-leninistisch), abbreviated KAO(ml)) was a communist group in the Netherlands. It was founded in March 1978, through the merger of the League of Dutch Marxist-Leninists (BNML), the Communist Workers Organisation (KAO) and the Communist Circle of Breda (marxist-leninist) (KKB(ml)). All of these had their origins in the pro-Chinese fraction of the Communist Party of the Netherlands.
The main organ of KAO(ml) was Rode Vlag (Red Flag).
KAO(ml) was active during the Rotterdam port strike of 1979.
KAO(ml) upheld the Three Worlds Theory promoted by the Communist Party of China. This eventually led to a split, with one section breaking away and forming the Workers Party of the Netherlands (build-up organisation) (Arbeiderspartij van Nederland (opbouworganisatie)) in 1980.
KAO(ml) dissolved around 1990.