Abstract: This study attempted to determine the academic achievement levels of mentally gifted sixth graders in the special accelerated and non – accelerated classes at the Davao City Special School, Philippines, based on the Special Education Regional Achievement Test Battery (SRATB – VI) results. The research made use of the descriptive documentary analysis of the regional achievement test results in four subjects, namely: English, Science and Health, Mathematics, and HEKASI (geography, history, and civics) covering three school years, 1996 – 1997, 1997 – 1998, and 1998 - 1999. It was found out that there were significant differences among the mean achievements of the two groups. It was concluded that the levels of achievements in the four subjects varied ranging from satisfactory to very satisfactory for the accelerated group while the levels of achievements for the non – accelerated classes varied ranging from moderate satisfactory to very satisfactory.