Background: Sleep disturbances are more common among sarcoidosis patients than in the general population. The influence of organ involvement on the subjective sleep quality was investigated in a large group of sarcoidosis patients. Methods: In collaboration with the German Sarcoidosis Association, 1197 sarcoidosis patients were examined with a specially developed questionnaire with the Pittsburgh sleep quality index (PSQI) integrated into it. Results: 91% had pulmonary involvement, 65% extra-pulmonary sarcoidosis. In 61%, two or more organs were involved. Subjective sleep quality in PSQI declined significantly (p < 0.001) with the increase in the number of organs involved; there was a significant increase in the prevalence of known sleep apnea (p < 0.005), restless legs syndrome (RLS), percentage of women and comorbidities (all p < 0.001). In at least 33% of patients with bone, muscle, nerve, kidney or heart involvement, the PSQI scores were > 10. Conclusions: In sarcoidosis patients with involvement of at least 2 organs, sleeping behaviour that includes RLS and sleep apnea should be evaluated.