Vocabulary learning is often perceived as boring by learners, especially for those who grew up in the digital age. This paper reports a study of the usefulness of online games in vocabulary learning for some undergraduate students. Three teachers and 100 engineering students participated in a quasi-experimental study for approximately nine weeks. The experimental group learnt some vocabulary from two carefully selected web sites with games, while the control group learnt the same vocabulary through activity-based lessons. A pre-test and post-test were conducted in the first and ninth weeks. The findings indicate that the experimental group outperformed the control group statistically in the post-test. The students in the experimental group generally preferred online learning supplemented with digital educational games to conventional activity-based lessons. The teachers thought highly of the online games, but they expressed concern that extra support was required if the online games were adopted as a core part of their teaching.[Copyright of Educational Media International is the property of Routledge. Full article may be available at the publisher's website: http://dx.doi.org/10.1080/09523980600641445]