Rodent damage to crops in developing countries is widely known. In Madagascar the most important rodent pest is the roof rat(Rattus rattus).The impact of the rat on rice crops was studied in the region of Lake Alaotra, the principal rice‐producing region of Madagascar. Evaluation of rodent damage was conducted in 591 parcels just before harvesting. The average damage value was low (on average less than 1%) and the average losses per hectare were also low at less than 100 kg paddy rice/ha. Differences were significant, depending on the locality and the presence of good refuge habitat for rats around the ricefield. The rice variety and agronomic practices did not influence the damage levels. The low damage level does not require the use of rodenticide in a rat control programme.