The Oldest known living thing is a bristlecone pine called Methuselah:


The Tree is called the Methuselah Tree, and it is the oldest living thing that we know about. It is a type of pine tree that grows in the White Mountains of Inyo County California. The oldest tree dates back to the year 2832 BC, making it 4843 years old, and its location remains undisclosed to protect it from vandalism!
The tree was discovered in 1957 by Edmund Schulman and Tom Harlan, and hassince been the marvel of scientists around the world.