Abstract: An apparatus for designing three-dimensional structures comprises a unit for recording linear coordinates having a movable support and guideways, crosspiece, carriage and vertical rod which are coupled to one another and which cause displacement along linear coordinates. Sensors of displacement along linear coordinates X, Y, Z are coupled to the guideways, crosspiece, carriage and vertical rod for causing displacement. The apparatus also has an angle joint having three series-connected angle arms for rotation with respect to X, Y, Z axes, respectively. Sensors for recording a change in an angular coordinate .phi., .phi..sub.1, .phi..sub.2, respectively, of rotation with respect to X, Y, Z axes, respectively, are coupled to the angle arms, the point of intersection of X, Y, Z axes of entered coordinates of the movable support coinciding with a point of intersection of X, Y, Z axes of the angle arms for rotation with respect to X, Y, Z axes, respectively.