Oils derived from plants have unique and distinct properties based on the compounds present. Prominent chemical compositions in different oils include fatty acids, tocopherols, tocotrienols and carotenoids. Different compounds can affect the regulation of gut immune response and barrier function. Feeds containing either crude palm oil (CPO), red palm oil (RPO), refined palm oil (RBD), palm kernel oil (PKO) and soybean oil (SBO) were fed to 150 laying hens. The feeding trial lasted for 16 weeks. Jejunum mucosa was collected at the end of week 16 to measure the proteins associated with barrier function using ELISA and genes related to immunity and barrier integrity by real-time polymerase chain reaction (PCR). In terms of barrier function proteins, various oils did not affect the concentration of intestinal trefoil factor (ITF) and diamine oxidase (DAO). However, the concentration of IgA was higher in CPO and RPO in contrast to SBO, and the alkaline phosphatase (ALP) concentration was higher in RPO and PKO. In terms of gene expression, the downregulation of genes related to immunity and barrier function genes was seen in CPO, RBD, RPO and PKO. Similar trends of lower regulation were observed in CPO and RPO than in other oils. Suppression of genes associated with immunity and barrier function would suggest reducing pathogens’ load and exposure to antigens in the gut. In conclusion, different sources of oil affect the regulation of intestinal mucosal immunity and barrier function.