Meteorus (Braconidae) is a large braconid genus which has global distribution, complex cocoon-suspension and gregariousness behaviours, and an unusual host range comprising several insect orders. Previous studies suggested classifying these behaviours into four simple states, e.g. “short or long silk” and “solitary or gregarious”, while we recognized 4 states for silk length and 5 for cocoon gregariousness. Since the variations of silk length and cocoon gregariousness are not correlated, 20 possible combinations of silk length and cocoon gregariousness are hypothesized but only 9 have been observed in the field and recorded in literature. In the present study we tested the hypothesis that gregariousness may increase conspicuousness of cocoons in predator’s eye using a visual ecological method, and infer the evolution of cocoon suspension and gregariousness by reconstructing the phylogeny of Meteorus. We simulated the visual condition of an agamid lizard to compare the colour contrast of UV reflection and visible light spectra between single cocoon, gregarious cocoons, wasps and environment. The result showed that the lizard’s vision could neither tell the cocoon from the environment nor the wasps from the cocoon no matter the cocoons were solitary or gregarious. Character evolution referred to the phylogeny based on 38 morphological characters from 33 Meteorus and Zele species reveals that different states of cocoon suspension and gregariousness may have evolved independently from solitary species. However, these intriguing behaviours can not be perfected interpreted by any of the current hypotheses due to insufficient information of their predators and biology.