The utility model relates to a bicycle expansion handle plug, which is suitable for most straight handlebars on the market, curved handlebars of highway vehicles, etc. Lightweight aluminum alloy material: the cover is made of aluminum alloy material, which makes the plug lighter, with smooth surface and rust prevention. Suitable size handlebar diameter: the inner diameter of handlebar shall be between 1.7cm-2.3cm/0.67in-0.91in. Lightweight design, zero load: a weight of about 18.6g, lightweight and portable, reducing the load and convenient to carry. Package content: 1 pair of black bicycle expansion handle plugs.