A positioning system (10) for positioning a patient (101) for diagnostic imaging is provided. The system comprises a sensor arrangement (12) with at least one sensor (14, 16) configured to provide a sensor signal indicative of at least one body parameter of the patient (101), a controller (18) configured to determine a value of the at least one body parameter based on the sensor signal of the at least one sensor (14, 16), and at least one actuatable support (20) configured to move at least one of an arm (105) and a leg (107) of the patient with respect to a torso of the patient. Therein, the controller (18) is configured to actuate the at least one actuatable support (20) depending on the determined value of the at least one body parameter to move at least one of the arm and the leg relative to the torso of the patient, such that the patient is guided to a posture for diagnostic imaging.