A work machine comprising: a head section (60, 62) configured to hold and move a lead component having a main body section, a pair of leads provided at a bottom of the main body section, and a mark portion indicating a polarity of the pair of leads; an imaging device configured to image a bottom of the lead component held by the head section; and a control device, wherein the control device comprises: a lead position detecting section configured to detect, based on imaged data imaged by the imaging device, positions of the pair of leads; a first detecting region setting section; a second detecting region setting section; and a polarity determining section characterized in that the first detecting region setting section is configured to set, based on the lead position detected by the lead position detecting section, a plurality of first detecting regions constituting regions outside the pair of leads included in a part of the bottom of the main body section; the second detecting region setting section is configured to set a plurality of second detecting regions constituting regions outside the pair of leads, being opposed to the first detecting section across the pair of leads, included in the part of the bottom of the main body section; and the polarity determining section is configured to determine the polarity of the pair of leads based on whether the mark portion exists in each of the first detecting regions and the second detecting regions. a head section (60, 62) configured to hold and move a lead component having a main body section, a pair of leads provided at a bottom of the main body section, and a mark portion indicating a polarity of the pair of leads; an imaging device configured to image a bottom of the lead component held by the head section; and a control device, wherein the control device comprises: a lead position detecting section configured to detect, based on imaged data imaged by the imaging device, positions of the pair of leads; a first detecting region setting section; a second detecting region setting section; and a polarity determining section characterized in that the first detecting region setting section is configured to set, based on the lead position detected by the lead position detecting section, a plurality of first detecting regions constituting regions outside the pair of leads included in a part of the bottom of the main body section; the second detecting region setting section is configured to set a plurality of second detecting regions constituting regions outside the pair of leads, being opposed to the first detecting section across the pair of leads, included in the part of the bottom of the main body section; and the polarity determining section is configured to determine the polarity of the pair of leads based on whether the mark portion exists in each of the first detecting regions and the second detecting regions. a lead position detecting section configured to detect, based on imaged data imaged by the imaging device, positions of the pair of leads; a first detecting region setting section; a second detecting region setting section; and a polarity determining section characterized in that the first detecting region setting section is configured to set, based on the lead position detected by the lead position detecting section, a plurality of first detecting regions constituting regions outside the pair of leads included in a part of the bottom of the main body section; the second detecting region setting section is configured to set a plurality of second detecting regions constituting regions outside the pair of leads, being opposed to the first detecting section across the pair of leads, included in the part of the bottom of the main body section; and the polarity determining section is configured to determine the polarity of the pair of leads based on whether the mark portion exists in each of the first detecting regions and the second detecting regions.