This study investigates domestic cat meows in different contexts and mental states. Measures of fundamental frequency (f0) and duration as well as f0 contours of 780 meows from 40 cats were analysed. We found significant effects of recording context and of mental state on f0 andduration. Moreover, positive (e.g. affiliative) contexts and mental states tended to have rising f0 contours while meows produced in negative (e.g. stressed) contexts and mental states had predominantly falling f0 contours. Our results suggest that cats use biological codes and paralinguistic information to signal mental state.