Amylose is a linear polymer of glucose linked with α(1→4) bonds. It can be made of several thousands glucose units. It is one of the two components of starch, the other being amylopectin.

The α(1→4) bonds promote the formation of a helix structure. The structural formula of amylose is pictured at right. The number of repeated glucose subunits (n) can be many thousands.

Amylose starch is less readily digested than amylopectin. The digestive enzyme amylase works on the ends of the starch molecule, breaking it down into sugars.