<p>Non-native species have attracted the attention of ecologists because of their impacts on natural resources and their relevance for testing ecological theories. The success of non-native species is affected by biotic and abiotic filters, whose effects depend on the spatial scale employed. This study tested the hypotheses that (i) native species richness and abiotic conditions explain the colonization of the non-native species <i>Hydrilla verticillata</i> and (ii) diversity-mediated biotic resistance varies across spatial scales. Plants were collected in October 2010, at 176 previously demarcated and georeferenced points in the Rosana Reservoir located at São Paulo State, Brazil. At each sampling site, measurements of <i>fetch</i>, reservoir width, organic matter and grain size, depth, Secchi disk depth, conductivity, pH, and species richness of submerged macrophytes at three spatial scales (small: 0.02m², medium: 240m², and large: 1200m²) were taken. The probability of occurrence of <i>H. verticillata</i> was positively correlated with increasing native species richness at all spatial scales, with no differences among scales, and with <i>fetch</i> and reservoir width. In contrast, occurrence was negatively related to sediment organic matter concentration and depth. These results indicate that biotic resistance did not reduce the invasion success of <i>H. verticillata</i>, and that competition did not influence its occurrence at small spatial scales. At present, abiotic factors may be more important than biotic resistance in determiningcolonization success in the reservoir, suggesting that invasion patterns of <i>H. verticillata</i> across spatial scales may reflect biotic acceptance in certain environments.</p>