The tolerance of the wolf spider Pardosa prativaga to two low quality prey types, the aphid Rhopalosiphum padi (Aphididae) and the collembolan Folsomia candida (Isotomidae), was tested in spiders with different nutrient balance. Good and bad nutrient balance was achieved by feeding the spiders fruit flics raised in cultures of different nutrient content. Spiders with a good balance consumed three times more R. padi than spiders with a bad balance, whereas there was no effect of nutrient balance on the tolerance to F. candida. The rejection behaviour to R. padi and F. candida was tested in spiders of good nutrient balance. The spiders ate more F. candida than R. padi before they refused to attack more prey. Spiders that accepted a fruit fly after the rejection of a low quality prey item were considered to have an aversion against such prey. Of the spiders given R. padi, 76% had or acquired an aversion to them. Only 5% of the spiders had or acquired an aversion to F. candida.