BackgroundAlthough the prevalence of pneumoconiosis has been decreasing due to improvements in working conditions and regular health examinations, occupational hygiene measures are still being established. Plasterers encounter a number of hazardous materials that may be inhaled in the absence of sufficient protection.Case presentationA 64-year-old man who plastered without any dust protection for more than 40 years was referred to our hospital with suspected interstitial pneumonia. Mixed dust pneumoconiosis and an unusual interstitial pneumonia (UIP) pattern with fibroblastic foci were diagnosed by video-assisted thoracoscopic surgery, and an elemental analysis detected elements included in plaster work materials. Despite the cessation of plaster work and administration of nintedanib, the patient developed advanced respiratory failure.ConclusionPlasterers are at an increased risk of pneumoconiosis and may have a poor prognosis when complicated by the UIP pattern. Thorough dust protection and careful monitoring are needed.Electronic supplementary materialThe online version of this article (10.1186/s12890-018-0776-4) contains supplementary material, which is available to authorized users.