The aim of the present work is to quantify the influence of alpha radioactivity of 225Ac doped UO2 on the dissolution rate under reducing conditions at pH 6. The doped or undoped material was prepared by precipitation and the size of particles was about 3 nm. The total alpha activity of the doped material was about 2000 MBq g-1 UO2, about 4 times higher than that of 15 years old spent fuel. The solution was kept under reducing conditions during the experiment by permanent electrochemical reduction under inert atmosphere. The results showed that the dissolution rate of doped material was a function of alpha activity and thus a function of the dose.