A work machine comprising: a frame of the work machine; an engine supported by the frame inside a machine compartment of the work machine; an exhaust emission control device including a filter that collects particulates contained in exhaust gas discharged from the engine; a compartment cover that defines the machine compartment; and a compartment cover supporting member that supports the compartment cover and is disposed on the frame; characterized in that: the work machine comprises: an engine hood that is supported by at least the compartment cover supporting member and includes a top plate shielding the machine compartment above the engine, an opening formed at the top plate, through which the exhaust emission control device is lifted up out of the machine compartment, and a reinforcing member (142, 143, 144, 145, 146) disposed at an edge of the opening, that bears a supporting load of the exhaust emission control device; an exhaust emission control device supporting member that suspends the exhaust emission control device downward through the opening and supports the exhaust emission control device in a suspended state; and an opening cover that is detachably mounted at the engine hood and closes off or opens up the opening, wherein: the exhaust emission control device supporting member includes a mounting portion that is attached to the exhaust emission control device and a fastening portion that is supported by, and fastened to, the reinforcing member (144, 145), and when the fastening portion is unfastened, the exhaust emission control device supporting member is removable above the opening together with the exhaust emission control device attached to the mounting portion. a frame of the work machine; an engine supported by the frame inside a machine compartment of the work machine; an exhaust emission control device including a filter that collects particulates contained in exhaust gas discharged from the engine; a compartment cover that defines the machine compartment; and a compartment cover supporting member that supports the compartment cover and is disposed on the frame; characterized in that: the work machine comprises: an engine hood that is supported by at least the compartment cover supporting member and includes a top plate shielding the machine compartment above the engine, an opening formed at the top plate, through which the exhaust emission control device is lifted up out of the machine compartment, and a reinforcing member (142, 143, 144, 145, 146) disposed at an edge of the opening, that bears a supporting load of the exhaust emission control device; an exhaust emission control device supporting member that suspends the exhaust emission control device downward through the opening and supports the exhaust emission control device in a suspended state; and an opening cover that is detachably mounted at the engine hood and closes off or opens up the opening, wherein: the exhaust emission control device supporting member includes a mounting portion that is attached to the exhaust emission control device and a fastening portion that is supported by, and fastened to, the reinforcing member (144, 145), and when the fastening portion is unfastened, the exhaust emission control device supporting member is removable above the opening together with the exhaust emission control device attached to the mounting portion. the work machine comprises: an engine hood that is supported by at least the compartment cover supporting member and includes a top plate shielding the machine compartment above the engine, an opening formed at the top plate, through which the exhaust emission control device is lifted up out of the machine compartment, and a reinforcing member (142, 143, 144, 145, 146) disposed at an edge of the opening, that bears a supporting load of the exhaust emission control device; an exhaust emission control device supporting member that suspends the exhaust emission control device downward through the opening and supports the exhaust emission control device in a suspended state; and an opening cover that is detachably mounted at the engine hood and closes off or opens up the opening, wherein: the exhaust emission control device supporting member includes a mounting portion that is attached to the exhaust emission control device and a fastening portion that is supported by, and fastened to, the reinforcing member (144, 145), and when the fastening portion is unfastened, the exhaust emission control device supporting member is removable above the opening together with the exhaust emission control device attached to the mounting portion. the exhaust emission control device supporting member includes a mounting portion that is attached to the exhaust emission control device and a fastening portion that is supported by, and fastened to, the reinforcing member (144, 145), and when the fastening portion is unfastened, the exhaust emission control device supporting member is removable above the opening together with the exhaust emission control device attached to the mounting portion.