Bonn is a prospering city with a young population. There are diverse possibilities for accommodation available for students, but since demand usually exceeds supply we recommend an early onset of your search.
Please be aware that usually the number of applicants exceeds the rooms available, so not every student will be allocated a dorm room. Therefore we suggest to all Incomings to start looking for private accommodation, even parallel to a pending application at the student union.

Studierendenwerk
First step for international students at the University of Bonn should be contacting the student union, which is responsible for the administration of the university's dormitories and accepts applications for dorm rooms.
http://www.studentenwerk-bonn.de/wohnen/

AStA
Online accommodation market by the General Students' Committee (AstA Bonn).
http://www.studenten-wg.de/partner/ASTA-Bonn.php

Hochschule Bonn-Rhein-Sieg
http://www.h-doppelpunkt.de/cms/wohnungsmarkt/wohnungsmarkt-startseite.html

Other student dormmitories
Other (commercial or ecclesiastical) providers of student dormitories in Bonn:.
http://www.dbh-bonn.de/
http://www.quartiervier.de/
http://www.quartiermitte.de/
http://www.quartierwest.de/
http://www.stella-matutina-ev.de/
http://miwo-student.de/

Internet Portal
Further commercial, but feeless websites for private accommodation.
https://www.uniplaces.com
http://www.wg-gesucht.de/wohnungen-in-Bonn.13.2.0.0.html
http://www.wg-spion.de/in/bonn
http://www.immobilo.de/mieten/bonn-stadt
http://www.zimmerfrei-bonn.de/wohnborse/suche/
http://www.studenten-wg.de/

Facebook
You may also check these facebook groups for accommodation offerings or post an ad yourself.
https://www.facebook.com/groups/465007710218892/
https://www.facebook.com/groups/460429377467077/
https://www.facebook.com/groups/281998241819457/
https://www.facebook.com/groups/324422547710247/

We wish you best of luck in your search!
Your Erasmus Student Network Bonn