A document scanning apparatus includes a controller configured to control an image scanner to scan a document sheet, thereby generating scanned image data, control a communication interface to transmit, to a storage, an instruction for inquiring whether there is one or more pieces of image data stored in a folder of the storage, control the communication interface to receive data existence information representing whether there is one or more pieces of image data stored in the folder, when the data existence information represents that there is one or more pieces of image data stored in the folder, control the communication interface to transmit, to the storage, an instruction to remove the one or more pieces of image data from the folder, and control the communication interface to transmit, to the storage, an instruction to store the scanned image data generated by the image scanner, into the folder.