Yes, you can.
It is best to use the uninstaller from Adobe. It is on this page:
Follow the instructions.
Because I am having problems with getting Flash Player that works on my pc, I have saved the Adobe Flash Player Uninstaller to my desktop. It is helpful not having to go back to the Adobe page to get it when I need it.
After uninstalling old versions of Flash Player, remember to check that the new version you keep is installed correcly and working properly, go to the Adobe "Find Version" page and follow the instructions there.
Hope this helps.
WRONG REDIRECTIONS !
It's the forum editor that sometimes mangles URL links. If you tell me your operating system, I will post the correct download links.