This paper is aimed at studying the optimum content of pre-treatment print paste used for ink-jet printing of wool fabric. Optimum condition of ink-jet printing with respect to the content of pre-treatment print paste and steaming time has been successfully developed through the orthogonal analysis. The parameters of the pre-treatment print paste including sodium alginate, urea and ammonium tartrate, as well as the post-treatment of steaming time right after ink-jet printing have been investigated. The optimum content of the pre-treatment print paste and the proper condition of post-treatment has been developed to achieve higher colour yield for cyan, yellow, magenta and black color (CYMK). The results of the highest colour yield obtained confirm that steaming time is the most dominating factor when compared with the other factors.