Will a journal reject my paper just because a grad student is the sole author? I have been working on a topic(numerical analysis) for several years, and I discovered something new which can be verified by numerical experiments. But my supervisor doesn't allow me to publish it, though he does admit that my research is worth publishing. 

So is it possible to publish my research without my supervisor? I have done the research all by myself, the idea, the numerical experiment is original and without any help from my supervisor, but I am still a student. Will the journal reject my paper just because I submit the paper while I am still a student and without any co-author?

As many people are wondering why my supervisor will not allow me to publish, I give my own explanation below:


He has a strong desire to control all the research in my lab, I am afraid he is the only person who is doing research in my lab, all the students who have published just wrote the articles, all the ideas are from my supervisor. All the ideas by the students usually will be abandoned.
I am an international student here, although I don't think that the relation with my supervisor is totally broken, I'm afraid he wants to postpone my graduation, so that he still have a PHD student in the next year. (Here is East-Asia, he can do like this without any opposition, it is not abnormal here as far as I know)


As someone suggested, my real problem may far beyond the simple question of the title. However, I do want to know if it is possible to publish a paper by a student solely. Of course any advice on whether I should or not publish my research is also appreciated.
Publishing paper does not necessarily need co-author and supervisor. However, it is strongly recommended. Having experienced co-author (not another unexperienced author) with couple of publications like your supervisor has several benefits, including:


Your co-author reads paper and puts effort to make it more professional and  mature for publication. He/she checks to ensure there is no mistake in technicality, presentation, and English.
It gives more confidence to reviewers to ensure that what you did is scientifically correct and is also producible. Though rejection of papers with several experienced authors is also a very common issue.


In research, there are several small hints and tiny things to consider that can impact on the final results/outcomes of the research. If you submit without your supervisor/advisor's, particularly without his help and actual supervision, it is very likely to have those error.

In reality, research is very much complex, though it might look very simple. There are many many things to consider before undertaking research, reporting it, and even trying to submit it. Thus, your idea might not be yet ready for publication yet. Your supervisor may want to help you do not get a quick rejection that discourages you.

I don't think that exist any supervisor on the earth that avoid publishing paper unless there is either threat to its credit or the work is premature. Your supervisor may exaggerate on the quality of your work/paper though it is not yet mature enough to encourage you. So, if he admit that your paper is good, it is not 100% sure that your paper is ready to publish at the moment. Remember that your supervisor can see lots of other things that you cannot see in this stage.

So the bottom-line is that, try to further work on your idea and convince your supervisor that the paper is good and he -as a normal humankind- should be more than happy to co-author the paper with you since publication is one of the main KPIs for academicians across the globe.