Chronic liver disease (CLD), such as hepatitis C, is a progressive disease consisting of the destruction and regeneration of the liver parenchyma, leading to fibrosis and cirrhosis. Platelets contain various growth factors and may play important roles in liver regeneration. Thus, to investigate whether platelet transfusion improves liver function in patients with CLD and cirrhosis, we conducted an exploratory clinical trial. The study included 10 patients with CLD and cirrhosis (Child-Pugh class A or B), who all presented thrombocytopenia (platelet counts between 50,000 and 100,000 /µl). The subjects received 10 units of platelet concentrate once a week for 12 weeks. They were followed up for 9 months after the last transfusion. One patient discontinued platelet transfusion because of pruritus, and 2 patients discontinued because of platelet transfusion refractoriness. One patient was excluded from the analysis for receiving a procedural treatment after 12 platelet transfusions. Thus, the remaining 6 patients were analyzed. The platelet count did not increase significantly after the last transfusion. Significant improvement of serum albumin was observed at 1 month and 3 months after the last transfusion. Serum cholinesterase improved significantly at 1 week, 3 months, and 9 months after the last transfusion. Serum hyaluronic acid showed a tendency toward improvement after the last transfusion. In conclusion, platelet transfusion improved some of the indicators of liver function in patients with CLD and cirrhosis, though adverse events related to platelet transfusion were observed in some patients. Platelet increment therapy could be a new strategy for treating CLD and cirrhosis.