A hammer unit of an electronic keyboard instrument to enhance working efficiency for assembling hammer members is provided. The hammer unit comprises a plurality of hammer members which apply loads to a plurality of keys, and a holding member which holds the plurality of hammer members. The holding member is configured to have one of a first holding state in which the plurality of hammer members are temporally locked at a first position and a second holding state in which the plurality of hammer members are released from the temporally locking at the first position.