The present technology relates to a data processing device, a data processing method, and a program capable of realizing low cost of a reception device receiving a GSE packet conforming to DVB-GSE. An sGSE packet structuring unit sets, as a target, only a PDU (Protocol Data Unit) of which a maximum size is restricted to a predetermined restriction size equal to or less than 4096 bytes and structures an sGSE packet which is a GSE packet in which the PDU is deployed in a data field and which conforms to DVB (Digital Video Broadcasting)-GSE (Generic Stream Encapsulation). The present technology is applicable, for example, when the GSE packet is transmitted or received.