Experiments were carried out on the laterality of hand and eye in two Rhesus monkeys. Trained monkeys in a primate chair had delayed to press a key on the left or on the right side indicated by a light on the left or on the right side. They could choose the left or right hand in these two cases. For the description of the results the terms "contralateral handedness" (monkey presses the left key with the right hand and the right key with the left hand) and "ipsilateral handedness" (monkey presses the left key with the left hand and the right key with the right hand) are defined. Eyedness of the monkeys in primate chair was demonstrated with a new eye-hand-coordination test. One monkey showed strong laterality (left-handedness and left-eyedness) but the other one with left-eyedness showed right-handedness during the key-pressing and also contralateral handedness. The conclusion is made that the combination of right-handedness and contralateral handedness in the test situation is a function of the left-eyedness in the monkey.