The objective of this work was to study the accelerated stability of Acetaminophen 500mg tablet sold on the Congolese market. Five specialties of Acetaminophen were examined: four locally manufactured generics and the innovator. Two analytical tests were made to study the change during the storage: The dosage of active ingredient by HPLC and dissolution profile by UV / Visible spectrophotometer. The results of this study reveal a problem with the manufacturing processes of Congolese generics. That is caused because they all present an abnormal drop of active ingredient and a release below the limit, from the sixth month of storage at a temperature and relative humidity of 40 °C and 75%.HR as per ICH guidelines.