Selkorinn Choir sang in wind and rain outside a window of the ward where Groa Petursdottir is a patient.
She missed four of the group's performances in Scotland after falling ill.
Staff at the hospital kept the arrangements of the hospital gig a secret from her.
Patients from other wards, including the children's ward, were also able to watch the performance from their windows.
The choir had to leave for home after completing its Scottish tour without Ms Petursdottir.
She said of their surprise performance: "It was very nice of them and a lovely surprise. I was very moved."
An Icelandic choir has performed a surprise gig at Raigmore Hospital in Inverness where one of its members has been receiving treatment.