Cytological investigation of woody tree species is apparently limited. For this reason, mitotic activity in root meristem of an endemic plant A. luzonensis naturally occurring in Mt. Banahaw de Dolores was investigated by microscopy using acetocarmine-squash technique. Seedlings of A. luzonensis were allowed to develop roots in a simple hydroponics set-up. The roots were processed following the standard protocol for cytogenetic investigation. To analyze the mitotic activity, a total of 728 cells were investigated and classified into different mitotic phases. From the result, the mitotic index is calculated to be 76.79% wherein the majority are in prophase stage (PI=73.08%). The metaphase cells were rarely seen with the lowest phase index recorded (PI=0.69%). This preliminary investigation offers a new possible research area for the establishment of chromosome number and comprehensive study about the cytogenetic characteristics of A. luzonensis.