This study aimed at analyzing Brazilian memes posted on Instagram about Covid-19, in which scientific concepts were intertwined with the message. The research was based on virtual ethnography and the analysis considered the multimodal structure of memes following principles of the Grammar of Visual Design. Only twelve memes out of a universe of 83 identified (14.5%) presented knowledge about science interdependently with meanings that could be produced. One of the core aspects is the complexity of both representations and scientific concepts in memes about Covid-19. Scientific aspects, humor and irony were associated with social and political criticism through different multimodal interactions.