A holding device for holding a substrate, the holding device comprising: an attracting unit having attraction mechanisms configured to vacuum-attract the substrate; pressure sensors (P1-P3) configured to measure pressure in the attraction mechanisms; and a control unit configured to: acquire reference data that includes time-dependent variation in pressure in the attraction mechanisms as a reference, in a case where the attraction mechanisms vacuum-attract a substrate based on a first sequence that indicates a sequence of the attraction mechanisms that start vacuum-attracting a first substrate; control the attraction mechanisms to vacuum-attract the first substrate based on the first sequence; control the pressure sensors to measure pressure in the attraction mechanisms while vacuum-attracting the first substrate based on the first sequence and acquire measurement data that indicates time-dependent variation in the measured pressure; acquire a comparison result by comparing the reference data and the measurement data and determine whether the comparison result satisfies a predetermined condition; control the attraction mechanisms, in case where the comparison result satisfies the predetermined condition, to vacuum-attract a second substrate based on the first sequence; and control the attraction mechanisms, in case where the comparison result does not satisfy the predetermined condition, to vacuum-attract the second substrate based on a second sequence different from the first sequence. an attracting unit having attraction mechanisms configured to vacuum-attract the substrate; pressure sensors (P1-P3) configured to measure pressure in the attraction mechanisms; and a control unit configured to: acquire reference data that includes time-dependent variation in pressure in the attraction mechanisms as a reference, in a case where the attraction mechanisms vacuum-attract a substrate based on a first sequence that indicates a sequence of the attraction mechanisms that start vacuum-attracting a first substrate; control the attraction mechanisms to vacuum-attract the first substrate based on the first sequence; control the pressure sensors to measure pressure in the attraction mechanisms while vacuum-attracting the first substrate based on the first sequence and acquire measurement data that indicates time-dependent variation in the measured pressure; acquire a comparison result by comparing the reference data and the measurement data and determine whether the comparison result satisfies a predetermined condition; control the attraction mechanisms, in case where the comparison result satisfies the predetermined condition, to vacuum-attract a second substrate based on the first sequence; and control the attraction mechanisms, in case where the comparison result does not satisfy the predetermined condition, to vacuum-attract the second substrate based on a second sequence different from the first sequence. acquire reference data that includes time-dependent variation in pressure in the attraction mechanisms as a reference, in a case where the attraction mechanisms vacuum-attract a substrate based on a first sequence that indicates a sequence of the attraction mechanisms that start vacuum-attracting a first substrate; control the attraction mechanisms to vacuum-attract the first substrate based on the first sequence; control the pressure sensors to measure pressure in the attraction mechanisms while vacuum-attracting the first substrate based on the first sequence and acquire measurement data that indicates time-dependent variation in the measured pressure; acquire a comparison result by comparing the reference data and the measurement data and determine whether the comparison result satisfies a predetermined condition; control the attraction mechanisms, in case where the comparison result satisfies the predetermined condition, to vacuum-attract a second substrate based on the first sequence; and control the attraction mechanisms, in case where the comparison result does not satisfy the predetermined condition, to vacuum-attract the second substrate based on a second sequence different from the first sequence.