The constant increase in the volume of fraud, that leave devastating effects on business performance, causes a significant preoccupation of enterprises with this problem. Being aware of the fact that the establishment of an adequate fraud risk management process is necessity, enterprises are increasingly basing the effectiveness of the mentioned process on the potentials of internal audit. Bearing in mind that internal audit does not have the primary responsibility to prevent and detect fraud, its integration in fraud risk management process represents a new challenge for this function. In the paper, authors initially point out the factors that determine the ability of the internal audit to fight against fraud, then the contribution that this function can provide in their prevention, detection and investigation.