The white grub beetle, Dasylepida ishigakiensis shows sex dimorphism in body dimensions and abundance of antennal sensilla. Body length was almost identical in the two sexes, but the abdomen was significantly longer in females than in males. Males had longer legs than females. Six types of sensilla were observed on antennal terminal lobes. The total number of sensilla on the inner surface of terminal antennal lobes was larger in males than in females. One type of sensilla showed a sex-specific size difference. Among individuals that were collected as third stadium larvae on Miyako Island, Okinawa, Japan and reared in the laboratory (n=527), three emerged as adults with asymmetrical antennae. One was found to represent a gynandromorph and the others were a male and a female with a deformed antenna.