| Cerdanyola del Vallès | |
| Settlement Type: | Municipality |
| Pushpin Map: | Spain Catalonia |
| Pushpin Label Position: | left |
| Pushpin Map Caption: | Location in Catalonia |
| Coordinates: | 41.4919°N 2.1389°W |
| Subdivision Type: | Country |
| Subdivision Name: |  Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Type2: | Province |
| Subdivision Name2: | Barcelona |
| Subdivision Type3: | Comarca |
| Subdivision Name3: | Vallès Occidental |
| Leader Party: | Socialists' Party of Catalonia |
| Leader Title: | Mayor |
| Leader Name: | Carlos Cordón Núñez (2019)[1] |
| Area Footnotes: | [2] |
| Area Total Km2: | 30.6 |
| Elevation M: | 32 |
| Population Density Km2: | auto |
| Population Demonym: | Cerdanyolenc, cerdanyolenca |
| Postal Code: | 08290 |
Cerdanyola del Vallès (pronounced as /ca/) is a municipality in the comarca of the Vallès Occidental in Catalonia, Spain. It is situated on the north side of the Collserola ridge. The town is served by the A-7 and C-58 motorways, the N-150 road and the Renfe railway commuter lines R4, R7 and railway regional line R12. It is well known as the site of the main campus of the Universitat Autònoma de Barcelona (at Bellaterra) and hosts the ALBA (synchrotron) located in the Barcelona Synchrotron Park.
As befits a municipality which has increased its population more than fiftyfold in the last century, most of the buildings are modern. The parish church is in a modernist style, while the Sant Marçal castle has been rebuilt in a neogothic style. The botanical gardens of El Pedregar (also at Bellaterra) have a notable collection of sculptures. Iberian remains have been found and are exposed at Ca n'Oliver Iberian Settlement and Museum.