Tetranychus viennensis (Zacher) feeds mainly on leaves and on flowers of fruit trees. It also feeds on the surface of developing fruits and may foul them with its webbing.

Hosts are mainly fruit trees of the family Rosaceae, in particular species of Crataegus (hawthorn), Cydonia (quince), Malus (apple), Prunus (blackthorn, cherry, peach, plum, apricot), and Pyrus (pear); also Chaenomeles (flowering quince), Rubus (raspberry: sporadic), and Sorbus (mountain ash).