The invention discloses an ink box with an automatic ink supplementing function. The ink box with the automatic ink supplementing function comprises an ink box body, a direct ink supplementing box body and an ink storage box body; the ink box body is arranged in a printer; the direct ink supplementing box body is arranged outside the printer, and the direct ink supplementing box body and the printer are located on the same horizontal plane; the internal space of the ink box body and the internal space of the direct ink supplementing box body are in the same shape; a lower hose is connected between the bottom of the ink box body and the direct ink supplementing box body, and an upper hose is connected between the top of the ink box body and the top of the direct ink supplementing box body;the ink storage box body is arranged outside the printer and located above the direct ink supplementing box body; a column-trough-shaped ink storage cavity is formed inside the ink storage box body; the internal space of the ink storage cavity and the internal space of the direct ink supplementing box body communicate through an ink supplementing pipeline; a supplementing opening and closing unitis arranged in the ink supplementing pipeline; when the supplementing opening and closing unit is located at the uppermost end, the ink supplementing pipeline is closed; and when the supplementing opening and closing unit is located at the lowest end, the ink supplementing pipeline is closed. Ink can be supplemented for the ink box automatically, and the effect that ink in the ink box is sufficient is ensured.