A tablet filling device for supplying a vial container of desired size certainly with no mistake comprising a plurality of containing means containing vial containers by size, a mean for taking out a vial container from the containing means based on prescription data, means for carrying a vial container taken out by the container take out means, a means or providing a table to a vial container carried by the carrying means, a means for collecting a vial container in the middle of carriage by the carrying means, a means provided on the carrying passage of the carrying means and detecting the size of a carried vial container, and a control means for judging whether the size of a vial container selected based on the prescription data matches the size of a vial container detected by the container size detection means and collecting the carried vial container by the container collection means if they do not match each other.