What GCSE grades do you need to get into oxford college?

Oxford University you mean? For GSCE: Usually at least 8 A*'s, all others A 3 A's at Alevel (might soon change to A*'s) I too want to go to Oxford, and this is what I was told, it can be higher or lower, but those are the average grades. Oh and GCSE's do matter, when looking to see if you will be good enough they look at them as you won't have your A Level result, without good GCSE's theres no use for good A Levels.

High ones. Preferably As or above. Although they probably won't stress if you get a couple Bs. Depends on what subject you want to take really. A Levels are most important. Most universities work with a points system. You get a certain number of points for each grade, and you have to get a certain amount to get into your course. This is the most important part. Then of course there's interviews, etc. etc. If you choose a course that is highly in demand, they will take your GCSEs into account. In this case, you'll want to have the best grades you can get.