A work machine comprising: a travelable track structure; a swing structure provided swingably on an upper side of the track structure; a work device coupled to a front side of the swing structure; a blade provided on a front side of the track structure such that the blade can be raised and lowered; and a lift cylinder that raises and lowers the blade, characterized in that the work machine includes a swing-structure-position acquiring device (31A, 31B, 32A, 32B) that acquires a horizontal coordinate and an orientation of the swing structure, a swing sensor (33A, 33B) that senses a swing of the swing structure, a travel sensor that senses travelling of the track structure, and a controller (35; 35A; 35B; 35C; 35D) that is configured to compute an orientation of the track structure, and a horizontal coordinate of the blade, and the controller (35; 35A; 35B; 35C; 35D) is configured to compute the orientation of the track structure by using a locus of the horizontal coordinate of the swing structure, the horizontal coordinate being acquired by the swing-structure-position acquiring device (31A, 31B, 32A, 32B), in a case where a swing of the swing structure is not sensed, and travelling of the track structure is sensed, and is configured to compute the horizontal coordinate of the blade on a basis of the computed orientation of the track structure, and the horizontal coordinate and the orientation of the swing structure acquired by the swing-structure-position acquiring device (31A, 31B, 32A, 32B). a travelable track structure; a swing structure provided swingably on an upper side of the track structure; a work device coupled to a front side of the swing structure; a blade provided on a front side of the track structure such that the blade can be raised and lowered; and a lift cylinder that raises and lowers the blade, characterized in that the work machine includes a swing-structure-position acquiring device (31A, 31B, 32A, 32B) that acquires a horizontal coordinate and an orientation of the swing structure, a swing sensor (33A, 33B) that senses a swing of the swing structure, a travel sensor that senses travelling of the track structure, and a controller (35; 35A; 35B; 35C; 35D) that is configured to compute an orientation of the track structure, and a horizontal coordinate of the blade, and a swing-structure-position acquiring device (31A, 31B, 32A, 32B) that acquires a horizontal coordinate and an orientation of the swing structure, a swing sensor (33A, 33B) that senses a swing of the swing structure, a travel sensor that senses travelling of the track structure, and a controller (35; 35A; 35B; 35C; 35D) that is configured to compute an orientation of the track structure, and a horizontal coordinate of the blade, and the controller (35; 35A; 35B; 35C; 35D) is configured to compute the orientation of the track structure by using a locus of the horizontal coordinate of the swing structure, the horizontal coordinate being acquired by the swing-structure-position acquiring device (31A, 31B, 32A, 32B), in a case where a swing of the swing structure is not sensed, and travelling of the track structure is sensed, and is configured to compute the horizontal coordinate of the blade on a basis of the computed orientation of the track structure, and the horizontal coordinate and the orientation of the swing structure acquired by the swing-structure-position acquiring device (31A, 31B, 32A, 32B).