To obtain the subject preparation capable of completely controlling the release of active ingredients and continuously releasing sodium tianeptine by combining a polymer originating from cellulose and a calcium salt.

This preparation is matrix tablets for continuously releasing sodium tianeptine prepared by using a polymer originating from cellulose (preferably methylhydroxy-propylcellulose) and a calcium salt (preferably calcium hydrogenphosphate dihydrate). The ratio between the cellulose derivative and the calcium salt is preferably in the range 30-50wt.% to 10-60wt.%, respectively, based on the whole weight of the tablets. By this matrix tablet, tianeptine is continuously released and as the result, the blood concentration of 50-300mg/ml is obtainable even at 24 hours after the administration in human.