A recording medium includes an ink-receiving layer on a substrate, in which the ink-receiving layer contains hydrated alumina, a C1-4 alkylsulfonic acid, and a salt of a compound of general formula (1): X1—R1—(S)n—R2—X2, wherein n represents 1 or 2; X1 and X2 each independently represent H, NH2, or COOH, and at least one of X1 and X2 represents NH2 or COOH; R1 and R2 each independently represent alkylene, arylene, or heteroarylene, and they may be bonded to each other to form a ring, upon letting the proportion of the C1-4 alkylsulfonic acid be A percent by mass with respect to hydrated alumina, A is in the range of 1.0 to 2.0, and upon letting the proportion of the salt of the compound of general formula (1) be B percent by mass with respect to hydrated alumina, B is in the range of 0.5 to 5.0.