A work machine operation apparatus that appropriately provides an operational feeling to an operator is provided. A base includes a plurality of first holes each having a first dimension. The base includes a plurality of second holes each having a second dimension different from the first dimension. An interval at which two adjacent first holes are arranged is different from an interval at which two adjacent second holes are arranged. A contact portion is in contact with the base. The contact portion can move relatively to the base and can selectively be engaged with any one of the plurality of first holes and the plurality of second holes. A biasing portion applies to the contact portion, biasing force in a direction in which the contact portion is brought in contact with the base. Upon accepting an input operation, an operational input portion moves the contact portion relatively to the base.