A survey of plant-inhabiting mites, Phytoseiidae and Tetranychidae, was carried out in 1988, 1989 and 2001 in some Moroccan crops, especially in vineyards near Meknes and in citrus orchards. Mites were also collected from uncultivated plants. Among the 15 phytoseiid mite species observed, 9 are new for the phytoseiid fauna of Morocco. One species of Tetranychidae, Panonychus ulmi (Koch), a serious pest mite all around the world, is recorded the first time from grapevines in Morocco.