Doijum (Dutch pronunciation: [ˈdoːi.ʏm]; West Frisian: Doaium) is a hamlet in the Dutch municipality of Waadhoeke in the province of Friesland.

It is located east of Hitzum, southeast of Kie and south of Franeker.

The residential area of the hamlet is located on the Franekerweg and Hitzumerweg, between the Binnenpad van Hitzum and the Lollummerweg where it eventually turns into the hamlet of Miedum.

It is spread over three settlements in terms of addressing; Hitzum, Franeker and Tzum.

In 1402 the hamlet was mentioned as Dodoghema buren and in 1406 as Do(e)deghum.