We evaluate how well environmental-economic models describe biodiversity loss and conservation issues. Four types of economic models turn out to dominate economic research into biodiversity conservation. For each of these, we assess the extent to which they integrate relevant ecological theories and indicators of biodiversity loss. A main conclusion is that models with more economic detail contain less detailed descriptions of the ecological dynamics of biodiversity change. We provide suggestions for improving economic models of biodiversity conservation and discuss the advantages of using less stylised representations of ecological processes.