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The effects of climate change on oaks <i>Quercus</i> spp. constitute a main environmental concern for the conservation of temperate forests. In this context, we assessed the consequences of longer droughts on the interactions between the holm oak <i>Quercus ilex</i> L. and its main acorn pests. Infested acorns were prematurely abscised before reaching their potential size. The volume of the acorns attacked by <i>Cydia fagiglandana</i> (Lepidoptera) was smaller than those attacked by <i>Curculio elephas</i> (Coleoptera); however, their weight did not differ because <i>Curculio</i> larvae consumed more cotyledon. For the same reason, embryo survival likelihood was not lower in <i>Cydia</i> acorns despite their smaller size. Delays of late summer rain reduced infestation by <i>Curculio</i>, as soil hardness hampers adult emergence from their underground cells. By contrast, late and scarce precipitations benefited <i>Cydia</i>; rainfall might hamper adult flight and eggs/L1 larvae survival. There was not a “zero-sum” effect, because the decrease of <i>Curculio</i> infestation rates was not fully compensated by an increase of <i>Cydia</i>. Under the longer droughts projected for the Mediterranean Basin, our results predict lower infestation rates and higher acorn survival likelihood. However, further studies including other environmental factors are needed to better forecast the net consequences for holm oak fitness.