The 21-year-old, who has also played on the wing, has progressed through Wigan's youth system.
Tierney is the son of former England dual-code international Jason Robinson, who also played for the Warriors.
"It is a huge achievement for me to agree this contract extension and I'm very happy to be staying at my hometown club," said Tierney.
His new deal also includes the option of a further year.
"Lewis is a good young Wigan kid who knows what it means to play for this great club," added head coach Shaun Wane.
"He has improved a greatly in the last few years and it excites me that there is still a lot more improvement to come."

The film star and his lawyer wife Amal, want to put up eight cameras on poles in the grounds, up to five metres (16ft) high.
They also wish to attach a further 10 cameras to the property.
The Eye and Dunsden Parish Council has concerns over privacy and the CCTV system's visual impact on the village.
David Woodward, chair of the council, said: "When you are strolling next to a pretty riverbank, it's a visual intrusion close to where people are walking."
Mr Woodward said the CCTV could also cause privacy concerns for Mr Clooney's neighbours.
The property at Sonning Eye is located on an island in the River Thames on the county line between Oxfordshire and Berkshire.
South Oxfordshire District Council's conservation officer recommends approval as long as the cameras can easily be removed from the building.
The district councillor has until Friday to decide whether to put the application before a planning committee.
Wigan Warriors full-back Lewis Tierney has signed a new three-year deal with the Super League side until 2019.
[NEXT_CONCEPT]
George Clooney's neighbours in Sonning have lodged objections to the star's plans to install 18 CCTV cameras at his Oxfordshire home.