Does a supervisor have right to submit paper without consents of coauthor students? Me and another PhD student, we are first two authors in a paper. We had a disagreement with our supervisor about submitting our paper to conference. We both opposed the submission as we think it's too early to submit our result and the paper will most likely be rejected. Our supervisor said, academically he has the full authority to submit the paper even if we oppose. My question is does a supervisor have the right to submit a paper from the point of view of the university?
Your supervisor does not have the right to submit a paper with your name as a coauthor without your consent. By making such a submission he would be making a false representation that all coauthors have agreed to the submission, thus essentially committing a form of minor fraud or certainly dishonest and unethical behavior that is considered completely unacceptable in the academic world.

Note that you write "from the point of view of the university", so technically there is a chance that your university has unconventional standards in such matters and in their eyes your supervisor is correct. If that is the case (which I strongly doubt), I would suggest getting the heck out of that miserable institution and going to a real university.

Finally, while it is absolutely possible that you generally have better judgment than your supervisor (a possibility that does not occur to many graduate students even when perhaps it should), he does have more -- probably a lot more -- experience than you in matters of publications, so I agree with jakebeal that it is worth questioning whether your objection to the submission is a good idea, and maybe consulting other experienced academics from your field.