The distribution and occurrence of mites collected from house dust in various climatic and altitudinal zones of Colombia were investigated. The most abundant mites collected were those of the family Pyroglyphidae, certain species of which have been shown to be producers of allergens. The families Acaridae, Glycyphagidae, Cheyletidae, and Chortoglyphidae were also common in the house dust. A majority of samples yielded more than IO mites per ml of house dust. Sites with mite loads of l ooo or more per ml were situated above l 400 meters in elevation. Detailed discussion is presented on the species of pyroglyphids, chortoglyphids, and cheyletids recovered from the bouse dust samples.