《三国志·蜀书·蒋琬费祎姜维传》
诸葛亮与留府长史张裔、参军蒋琬写信说： 姜伯约对时事非常的忠心勤奋，思虑周全，考察他的德行，永南、季常等人都比不上他，这个人是凉州的上等之人。 
亮与留府长史张裔、参军蒋琬书曰： 姜伯约忠勤时事，思虑精密，考其所有，永南、季常诸人不如也。其人，凉州上士也。 
Zhuge Liang wrote to Liu Bei's staff history Zhang Yi and participants Jiang Wan: "Jiang Boyue is very loyal and hardworking to current affairs, and he is well-considered. In terms of his virtues, Yongnan, Jichang, and others are not as good as him. This man is a superior man in Liangzhou."