A kind of flexible nipple structure,It includes: a nipple is formed with a coupling collar,Again the nipple with combine circumferential one end be sequentially extended with a collection milk section,One bending segment and an occlusion section,It is formed with an outer convex curve between the bending segment and collection milk section,And the bending segment is formed with an inner concave bending pars convoluta with being engaged between section,Make collect milk section,Bending segment and the section composition for being engaged section have a Z-shaped shape,The thickness of the collection milk section is in gradually-reducing shape from coupling collar end to bending segment again,And the thickness of the occlusion section is in gradually-reducing shape to bending segment direction,The maximum gauge of collection milk section and all big what bending segment of the maximum gauge for being engaged section is enabled,The retractility of nipple is thereby improved using relatively thin bending segment.一種伸縮奶嘴結構，其包括有：一奶嘴形成有一結合環，又該奶嘴以結合環向一端依序延伸有一集奶段、一彎折段及一咬合段，該彎折段與集奶段之間形成有一外凸彎曲部，而該彎折段與咬合段之間形成有一內凹彎曲部，使集奶段、彎折段及咬合段之斷面構成有一Z字型狀，又該集奶段之厚度由結合環端向彎折段呈漸縮狀，且該咬合段之厚度向彎折段方向呈漸縮狀，令集奶段與咬合段之最大厚度皆大於彎折段之最大厚度，藉此利用較薄的彎折段提高奶嘴之伸縮性。
