Using conformal representation, the oil flow coefficient of the pressure-fed journal bearing with an axial oil groove is calculated. Though the graphical conformal mapping by Wilcock and Rosenblatt gives merely the data for particular forms of the groove, the coefficient for any value of l/L and b/L can be obtained by this analytical method where l and b are the length and width of the groove respectively, and L is the axial length of the bearing. And also the coefficient for nearly circular hole is simply calculated.