We designed a working memory (WM) training programme in game framework for mild intellectually disabled students. Twenty-four students participated as test and control groups. The auditory and visual-spatial WM were assessed by primary test, which included computerised Wechsler numerical forward and backward sub-tests and secondary tests, which contained three parts: dual visual-spatial test, auditory test and a one-syllable word recalling test. The results showed significant difference between WM capacity in the intellectually disabled children and normal ones (p-value?<?0.00001). Visual-spatial WM, auditory WM and speaking were improved in the trained group. Four tests showed significant differences between pre-test and post-tests. The trained group showed more improvements in forward tasks. The trained participant's processing speed increased with training.