The present application discloses a method and device for forwarding a data message. A specific embodiment of the method comprises: receiving the data message and reading a data context length value of a first row in the data message; determining whether the data context length value is less than or equal to a maximum segment size in a single transmission according to a transmission control protocol; reading data from the data message in segments in response to the data context length value being less than or equal to the maximum segment size in the single transmission according to the transmission control protocol; reading data from the data message in rows in response to the data context length value being greater than the maximum segment size in the single transmission according to the transmission control protocol; and storing the read data in a user buffer, and sending the data in the user buffer to a terminal if the data in the user buffer exceeds a preset capacity threshold. According to this embodiment, the data messages can be quickly and efficiently forwarded.