The disclosure provides a method and system for sending a short message. The method includes: an SMS-SC sending a short message to an SMS-GMSC, and after the SMS-GMSC sends the short message to an MME, the MME sending a failure report to the SMS-GMSC when the MME detects that a terminal is unreachable (S202); the SMS-GMSC receiving the sent failure report and sending a short-message sending status message to an HSS, and the HSS setting waiting data according to the short-message sending status message (S204); upon detecting that the terminal switches from unreachable to reachable, the MME notifying the HSS that the terminal is reachable (S206); upon learning that the terminal is reachable, the HSS sending, according to the waiting data, a warning message to notify the SMS-SC that the terminal is reachable, and upon learning that the terminal is reachable again, the SMS-SC sending the short message again (S208). By means of the solution, a short message service can also be received in an area covered only by a packet switched network.