An articulated robot is provided with first, second and third arms respectively having effective lengths substantially equal to each other and capable of turning respectively about first, second and third pivotal axes. The second and the third arm are interlocked by an interlocking mechanism such that the third arm turns about a third pivotal axis relative to the second arm in one of opposite directions through an angle twice as large as an angle through which the second arm turns about a second pivotal axis relative to the first arm in the other direction. The second arm 25 and the third arm 26 are moved in either of first and second working areas respectively extending on the opposite sides of an imaginary plane including a reference line and the first pivotal axis to move hand units along the reference line. Since the second and the third arm are necessarily only in one of the first and the second working region, the articulated robot is capable of operating in a narrow working area.