A board work machine comprising: a board fixing device configured to fix a board; a board work device configured to perform work with respect to the board fixed by the board fixing device; an imaging device configured to image a surface of the board fixed by the board fixing device; a control device configured to recognize an imaging target as a reference mark (FM1;FM2) in a case in which a position deviation amount (ΔX,ΔY,ΔL) of the imaging target imaged by the imaging device is within a set tolerance (TΔX1,TΔY1,TΔL1;TΔX2,TΔY2,TΔL2), and control the board work device to perform work using the recognized reference mark (FM1;FM2) as a reference, characterized in that in a case in which the board fixed by the board fixing device is a board provided with an overall reference mark that represents a reference of the board overall and a local area reference mark that represents a reference of a local area, the set tolerance (TΔX2,TΔY2) for recognizing the local area reference mark is smaller than the set tolerance (TΔX1,TΔY1) for recognizing the overall reference mark, and in a case in which the board fixed by the board fixing device is a board on which a pair of overall reference marks (FM1,FM1) separated from each other is provided as the overall reference mark, and a pair of local area reference marks (FM2,FM2) that are separated from each other is provided with respect to one local area as the local area reference mark, the set tolerance (TΔX1,TΔY1,TΔL1) for recognizing the overall reference mark, as a set tolerance of the relative position deviation amount (ΔL) of the pair of overall reference marks (FM1,FM1), includes a set tolerance (TΔL1) with respect to a separation distance of the pair of overall reference marks (FM1,FM1), and the set tolerance (TΔX2,TΔY2,TΔL2) for recognizing the local area reference marks (FM2,FM2), as a set tolerance of the relative position deviation amount (ΔL) of the pair of local area reference marks (FM2,FM2), includes a set tolerance (TΔL2) with respect to a separation distance of the pair of local area reference marks (FM2,FM2), and the set tolerance (TΔL2) with respect to the separation distance of the pair of local area reference marks (FM2,FM2) is smaller than the set tolerance (TΔL1) with respect to the separation distance of the pair of overall reference marks (FM1,FM1). a board fixing device configured to fix a board; a board work device configured to perform work with respect to the board fixed by the board fixing device; an imaging device configured to image a surface of the board fixed by the board fixing device; a control device configured to recognize an imaging target as a reference mark (FM1;FM2) in a case in which a position deviation amount (ΔX,ΔY,ΔL) of the imaging target imaged by the imaging device is within a set tolerance (TΔX1,TΔY1,TΔL1;TΔX2,TΔY2,TΔL2), and control the board work device to perform work using the recognized reference mark (FM1;FM2) as a reference, characterized in that in a case in which the board fixed by the board fixing device is a board provided with an overall reference mark that represents a reference of the board overall and a local area reference mark that represents a reference of a local area, the set tolerance (TΔX2,TΔY2) for recognizing the local area reference mark is smaller than the set tolerance (TΔX1,TΔY1) for recognizing the overall reference mark, and in a case in which the board fixed by the board fixing device is a board on which a pair of overall reference marks (FM1,FM1) separated from each other is provided as the overall reference mark, and a pair of local area reference marks (FM2,FM2) that are separated from each other is provided with respect to one local area as the local area reference mark, the set tolerance (TΔX1,TΔY1,TΔL1) for recognizing the overall reference mark, as a set tolerance of the relative position deviation amount (ΔL) of the pair of overall reference marks (FM1,FM1), includes a set tolerance (TΔL1) with respect to a separation distance of the pair of overall reference marks (FM1,FM1), and the set tolerance (TΔX2,TΔY2,TΔL2) for recognizing the local area reference marks (FM2,FM2), as a set tolerance of the relative position deviation amount (ΔL) of the pair of local area reference marks (FM2,FM2), includes a set tolerance (TΔL2) with respect to a separation distance of the pair of local area reference marks (FM2,FM2), and the set tolerance (TΔL2) with respect to the separation distance of the pair of local area reference marks (FM2,FM2) is smaller than the set tolerance (TΔL1) with respect to the separation distance of the pair of overall reference marks (FM1,FM1). the set tolerance (TΔX1,TΔY1,TΔL1) for recognizing the overall reference mark, as a set tolerance of the relative position deviation amount (ΔL) of the pair of overall reference marks (FM1,FM1), includes a set tolerance (TΔL1) with respect to a separation distance of the pair of overall reference marks (FM1,FM1), and the set tolerance (TΔX2,TΔY2,TΔL2) for recognizing the local area reference marks (FM2,FM2), as a set tolerance of the relative position deviation amount (ΔL) of the pair of local area reference marks (FM2,FM2), includes a set tolerance (TΔL2) with respect to a separation distance of the pair of local area reference marks (FM2,FM2), and the set tolerance (TΔL2) with respect to the separation distance of the pair of local area reference marks (FM2,FM2) is smaller than the set tolerance (TΔL1) with respect to the separation distance of the pair of overall reference marks (FM1,FM1).