Mixed connective tissue disease, one of the autoimmune rheumatological diseases, is a rare occurrence and its etiology has not been fully established. Its association with silicosis is much rarer, but it is an interesting condition that merits examination. Our case is a 45-year-old male patient who was diagnosed with silicosis in the seventh year of working in a quartz surface mine, and three years after his silicosis diagnosis, he developed rheumatological complaints and was diagnosed with mixed connective tissue disease. In this case, we wanted to draw attention to the coexistence of silicosis and mixed connective tissue disease. Based on the literature, although it is a rare association, it suggests that silica particles may play a role in the etiology of the disease.