In total 30 days of October and November 2012, the authors conducted study on recording the songs of 24 samples from 13 groups of Northern buffed-cheeked (Nomascus annamensis) and 13 groups of gibbons in 3 compartments out of 10 compartments (2km x 2km), which located in 25 and 12 forest compartment at Quang Nam Sao la Nature Reserve. 5 samples from these 24 samples were duplicated recorded, 6 sing samples were collected from outside the protected area. Northern buffed-cheeked (Nomascus annamensis) distributed only in the big tree forest. the acoustic analysis of northern buffed-cheeked (Nomascus annamensis) in Quang Nam Sao la Nature Reserve is the first one.