Provided is a position detection system capable of assessing the polarity of a sensing coil without complicating the configuration of a capsule medical device. A position detection system is provided with a plurality of sensing coils (32(i)) which detect an alternating-current magnetic field generated from a marker coil and output detection signals, respectively and an operation unit (46) which calculates the position of a capsule endoscope (10) on the basis of the plurality of detection signals respectively outputted from the plurality of sensing coils (32(i)), and the operation unit (46) comprises a reference coil determination unit (462) which determines, as a reference coil, a sensing coil having the maximum amplitude value among the plurality of sensing coils (32(i)) on the basis of the amplitude values of the alternating-current magnetic field detected by the plurality of sensing coils (32(i)), the amplitude values being calculated on the basis of the plurality of detection signals, and a polarity assessment unit (463) which assesses the polarity of each of the sensing coils (32(i)) on the basis of a first detection signal outputted by the reference coil and a second detection signal outputted by each of the sensing coils (32(i)) other than the reference coil.La présente invention concerne un système de détection de position capable dévaluer la polarité dune bobine de détection sans compliquer la configuration dun dispositif médical à capsule. Un système de détection de position est pourvu dune pluralité de bobines de détection (32(i)) qui détectent un champ magnétique à courant alternatif généré par une bobine de marquage et des signaux de détection de sortie, respectivement et une unité opérationnelle (46) qui calcule la position dun endoscope à capsule (10) sur la base de la pluralité de signaux de détection respectivement transmis par la pluralité de bobines de détection (32(i)) et lunité opérationnelle (46) comprend une unité de détermination de bobine de
