In accordance with Article 6 of Regulation (EC) No 396/2005, the evaluating Member State, Italy, received an application from Syngenta to modify the existing maximum residue level (MRL) for the active substance penconazole in grapes. The data submitted in support of the request are sufficient to derive a MRL proposal of 0.4 mg/kg for the intended use on grapes. Adequate analytical enforcement methods are available to control the residues of penconazole in grapes. Based on the risk assessment results, EFSA concludes that the intended use of penconazole on grapes will not result in a consumer exposure exceeding the toxicological reference values and therefore is unlikely to pose a consumer health risk. However, these results should be considered provisional due to the fact that the risk assessment for triazole derivate metabolites is still pending.