How to uninstall OpenOffice?

Go to Synaptic Package Manager and choose the part installed packages to list out only installed packages

then, Search on OpenOffice

Mark all OpenOffice packages that are found for complete removal by right-clicking on them.

Do the same thing searching OO3

Or Run

sudo apt-get remove openoffice*.*

Open a terminal, type in the following command and follow the on-screen instructions:

sudo aptitude purge openoffice.org

If you don't already have the aptitude package installed, you can do so by:

sudo apt-get install aptitude

The advantage of aptitude over apt-get is that it installs all needed dependencies automatically when installing a package, and it removes all obsolete dependencies automatically that aren't needed anymore.