Provided are a quinuclidine derivative of formula (1) and a medicament comprising the quinuclidine derivative:wherein R1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a haloalkyl group, a lower alkoxy group, or a haloalkoxy group; Y represents —C(C═O)—O—, or —CH2O—; m represents an integer of 1 to 5; Z represents an oxygen atom or a sulfur atom; l represents a number of 0 or 1; n represents an integer of 0 to 4; X− represents an anion; and a substituent of a quinuclidine ring represents a 1,3-bond, or 1,4-bond, provided that when m is 3, l is 1, and n is 0, R1 represents a halogen atom, a lower alkyl group, a haloalkyl group, a lower alkoxy group, or a haloalkoxy group.