Fermented liquid feed (FLF) protects broiler chickens against colonisation with Salmonella. While Campylobacter causes more disease cases in humans than Salmonella, the effect of FLF on Campylobacter was assessed. The fermented liquid feed is a moistened feed with a high number of lactobacilli, a high concentration of lactic acid, and a pH of 4. In three experiments Campylobacter was orally applied to individually housed 9-day-old broiler chickens. A significant reduction of susceptibility, as determined by cloacal swabs, was observed. At any moment where an animal has not started to shed Campylobacter yet, the probability to start shedding Campylobacter in a subsequent small time interval was nine times as high for the control chickens than for the animals that were fed FLF. FLF did not consistently change the Campylobacter colonisation level in the caeca. It was concluded that FLF could reduce the probability of introduction of Campylobacter in broiler flocks. In an experiment where some chickens were simultaneously inoculated with Salmonella enteritidis and Campylobacter, no interaction on susceptibility or caecal colonisation level was observed.