The spread of poetry by way of ancient postal service in Tang dynasty is an important subject in studying the development of Tang poetry. The ancient postal system in Tang dynasty included both water route and land route which covered every corner of the country, formed a highly developed and strict system. Besides transmitting government decrees and transporting officials and goods, the ancient postal service also helped the development of Tang poetry. Many historical documents proved that ancient postal service in Tang dynasty ensured an immediate transportation between poets and contributed to the wide-spread of the poetry, and it also served as a bridge between the poets who were in great distance and then helped to form different poetry schools and fashion.