There are 2 ways.
From the 5.0 PPA (recommended):
sudo add-apt-repository ppa:libreoffice/libreoffice-5-0
sudo apt-get update
sudo apt-get install libreoffice
.deb files (not recommended):
First, visit the Download page. To jump to the
.deb version for 64 bit click here, or for 32 bit click here.
Next, click Download. Consider using the Torrent file as it reduces the load on their servers.
When the 229 MB download is finished (which will take 9.5 hours on dial up or 7 minutes on a High Speed T3 connection) you will need to extract the
Navigate to the file in your file manager, right click and chose "Extract Here".
Open a terminal and run this command:
Then, as the
README says you need to run this command:
sudo dpkg -i *.deb
This will take a while, but when the command finishes, you will have Libre Office 5.0