To provide an optical glass having a high refractive index and a high dispersion characteristic, and suitable for precision press molding, a preform for precision press molding, and their manufacturing method, and an optical element made from the optical glass and its manufacturing method. Solution This optical glass is a phosphate optical glass containing P<SB>2< / SB>O<SB>5< / SB>, Bi<SB>2< / SB>O<SB>3< / SB>, Nb<SB>2< / SB>O<SB>5< / SB>, and TiO<SB>2< / SB>as essential components, containing 12-34% P<SB>2< / SB>O<SB>5< / SB>, more than 6% but not more than 28% Bi<SB>2< / SB>O<SB>3< / SB>, less than three times the content(mol%) of Bi<SB>2< / SB>O<SB>3< / SB>Nb<SB>2< / SB>O<SB>5< / SB>, 0-28% Li<SB>2< / SB>O, and 0-16% Na<SB>2< / SB>O in mol%, and having a refractive index (n<SB>d< / SB>) of greater than 1.85. This optical glass is a phosphate optical glass containing 12-34% P<SB>2< / SB>O<SB>5< / SB>, more than 6% but not more than 28% Bi<SB>2< / SB>O<SB>3< / SB>, less than three times the content(mol%) of Bi<SB>2< / SB>O<SB>3< / SB>Nb<SB>2< / SB>O<SB>5< / SB>, more than 0% but not more than 30% TiO<SB>2< / SB>, 1-40% WO<SB>3< / SB>, 0-28% Li<SB>2< / SB>O, 0-16% Na<SB>2< / SB>O, and 0-14% B<SB>2< / SB>O<SB; >3< / SB>in mol%, and having a refractive index (n<SB>d< / SB>) of greater than 1.85.