Provided is a zoom optical system which includes, in order from an object, a first lens group having negative refractive power and other lens groups, and in which an interval between each lens group changes upon zooming, wherein the first lens group includes a first negative lens which is disposed closest to the object and has a diffractive optical element on an image side lens surface, and a positive lens disposed closer to the image than the first negative lens, and the glass material used for the positive lens satisfies the following conditions expressions: 1p35 and (g, F)0.007, where 1p denotes an Abbe number, based on the d-line, of the glass material used for the positive lens of the first lens group, and (g, F) denotes a deviation of the partial dispersion ratio of the glass material, which is used for the positive lens, from a standard line that connects a glass type A and a glass type B in a graph of which abscissa is an Abbe number d based on the d-line, and the ordinate is the partial dispersion ratio (g, F)=(ngnF)/(nFnC), with the Abbe number d and the partial dispersion ratio (g, F) of the glass type A and the glass type B being as follows: Glass type A: d=60.49, (g, F)=0.5436; glass type B: d=36.26, (g, F)=0.5828.

A zoom lens includes a first lens unit having a negative refractive power, a second lens unit having a positive refractive power, and two or more additional lens units. In zooming, the first lens unit moves, and an interval between adjacent lens units changes. The refractive index of a negative lens A disposed on a most object side of negative lenses included in the first lens unit is higher than or equal to 1.89, and the negative lens A and a lens B disposed adjacent to an image side of the negative lens A satisfy a predetermined relationship.