An instrument system for minimally invasive surgery in single port technology, having a trocar and at least one instrument channel (28) which runs at the trocar from proximal to distal and a proximal end remaining extra-corporally when the trocar is inserted into the body of a patient, and a distal end located intra-corporally, wherein a semi-flexible instrument (38) can be inserted through the instrument channel (28) in such a manner that the operating handle (40) thereof remains extra-corporal and the distal working element (42) thereof emerges distally from the instrument channel (28). The instrument channel (28) is flexibly pliant, stable in the longitudinal direction thereof and arranged outside on the trocar. The distal end (30) of the instrument channel is fixed to the trocar. The instrument channel (28) is axially displaceable by means of a middle section in a guide on the trocar, with the result that the instrument channel (28) is bent out sideways from the trocar in the length region (36) thereof between the fixed distal end (30) and the guide on the trocar, when the instrument channel (28) in the guide is pushed towards distal. The instrument channel (28) has an outlet opening (44) for the distal end of the instrument (38), which is located in the bent out length regions (36) displaced from the fixed distal end (30) in the proximal direction.
