The present technology relates to a transmission device, a transmission method, a reception device, and a reception method, whereby an IP packet can be efficiently broadcast and rapidly processed. A transmission packet including an IP packet is transmitted and received. A header of the transmission packet is composed of type information indicating whether an IP header and a UDP header are compressed, and length information indicating the length of the transmission packet for transmitting the IP packet including a UDP packet. A payload of the transmission packet is composed of a destination IP address and a destination port number, or a destination index associated with the destination IP address and the destination port number, and a payload of the UDP packet. The present technology is applicable, for example, to broadcasting of the IP packet.