Will my citizenship be affected if I had an arrest about 7 years ago for possession of marijuana and I was given a conditional discharge?

Generally, possession of marijuana has severe immigration law consequences. Depending on the circumstances, USCIS might not only deny an application for naturalization but also start a deportation process. To tell you how your particular history will likely influence the outcome of your naturalization application, it is necessary to know how much marijuana you had (more or less than 30 grams), did you plead guilty, did the court enter a conviction or were the charges dismissed after the conditional period, and if you were convicted, what was the statute of conviction (sometimes, the conviction is different from the arrest charges; for instance, an arrest for a simple possession of marijuana might lead to a conviction for disorderly conduct) You should discuss your situation with an immigration attorney before filing your application for naturalization.

Your question requires an attorney consultation. It is not a simple question that can be answered on this type of forum. There are many factors that would need to be considered and evaluated. The short answer is that it can depending on the amount of marijuana and how the conditional discharge was arranged.