A hybrid bicycle is a compromise between a road bicycle and a mountain bicycle.

A relatively recent type of bicycle, the hybrid aims to retain the features of mountain bicycles which have made them accessible and popular, but are designed to be more suitable for urban use.

The hybrid can be thought of lying somewhere between the road bicycle and the mountain bicycle and each manufacturer is free to bias their hybrid closer to one type or the other. This makes it difficult to define precisely what a hybrid is.

In general, all hybrids will use mountain bike gears to make riding in hilly environments easier, and will have an upright riding position similar to a mountain bike.

Road-biased hybrids will usually have 700C rims with slick tires between 32 and 40 mm wide. This additional tire width over a road bicycle is intended to give the hybrid some ability to deal with rough surfaces that might be encountered on bike trails, such as gravel, hard-packed sand and shallow mud. Mountain-biased hybrids usually have 26 inch rims with semi-slick tires around 1.95 inches wide.

Handlebars are neither downturned like a road bicycle nor flat like a mountain bicycle. Rather, they have a slight upturn, providing for a more upright seating position.

A subclass of the hybrid category is the comfort bike. The difference is more one of marketing focus than specification, but such features as front suspension forks, seat post suspension and angle-adjustable stems may be provided to enhance the comfort of the rider.