The present invention relates to a short sentence transmission method and system, a server, a sending client, and a receiving client. The method comprises the steps that the server determines whether a short sentence transmitted by the sending client is compressed; if the short sentence transmitted by the sending client is compressed, the server uses a first session record to decompress the short sentence transmitted by the sending client, so as to obtain an original transmitted text, wherein the first session record is a session record of the sending client; the server uses a second session record to compress the original transmitted text, so as to obtain a to-be-transmitted short sentence, wherein the second session record is a session record of the receiving client; and the server sends the to-be-transmitted short sentence to the receiving client, so as to enable the receiving client to acquire the original transmitted text through the to-be-transmitted short sentence. Through adoption of the method, the short sentence is better compressed, and less bandwidth and traffic are consumed for transmission of the short sentence.