An object of the present invention is to provide a core shell particle having high luminous efficacy and a narrow emission half-width; a method of producing the same; and a film formed of the core shell particle. The core shell particle of the present invention includes: a core which contains a Group III element and a Group V element; a first shell which covers at least a part of a surface of the core; a second shell which covers at least a part of the first shell; and a coordination molecule in at least a part of an outermost surface, in which at least oxygen is detected by X-ray photoelectron spectroscopy analysis, and a molar ratio of the oxygen to the Group III element contained in the core, which is acquired by X-ray photoelectron spectroscopy analysis, is 6.1 or less.