A sealant applying apparatus includes a fastener rotating unit which supports a fastener to be rotatable around a central axis, and a sealant discharging unit which applies a sealant to the fastener by discharging the sealant. The fastener rotating unit includes a first holding member and a second holding member which hold the fastener to be rotatable, and a base which supports the first and second holding members. The first holding member is installed to the base to be exchangeable.