This research aimed to determine the different benthic macro-invertebrates present in the Pinacanauan de Ilaguen and Diden River Systems located at the Northern Sierra Madre Mountain Range as well as their physico-chemical properties. Results of the study showed that, among the major sampling stations in the Pinacanauan de Ilaguen River, the upstream station has the highest number of genera with 25 and with 246 individuals. The index of diversity in this station on the genus level is 2.57 while the genus evenness is 0.47 which means that the organisms are not equally distributed in the area and the value of genus dominance is 0.88. In this station, the most dominant macro-invertebrate in the genus level is Heptagenia (Mayfly) having a total of 62 (25.20%) individuals Some organisms were unidentified in terms of their common name and the genus where they belong. It was found out also that there is a significant positive relationship between the diversity index and water conductivity considering the two river systems. This is contradictory to the expected outcome because diversity of organisms in water is expected to increase with a decrease in the value of water conductivity since water conductivity indicates pollutant load in the water. However, this result may indicate that the pollutant load condition of the river systems have not yet reached their critical levels that can markedly manifest in the levels of water conductivity.