The forward, who previously played for Rangers, St Mirren, and Livingston, joins the club from Plymouth Argyle for an undisclosed fee.
The 28-year-old, who scored 74 goals in 248 games for Plymouth, has signed a contract with the Welsh side until the end of the 2027/28 season.
After his move to the Championship team, Hardie said: “I’m delighted to get the move done, I’m really happy to get it done so early and I cannot wait to get going.
“To get a full pre-season will be a massive benefit, to get integrated into the squad and learn the way the manager plays and get to know everyone will be important.”
Hardie, who hails from Stranraer, started his career at Rangers, making his debut in 2014.
He then went on to make appearances for St Mirren, Raith Rovers, and Livingston.
He has also played for Blackpool.
Wrexham AFC manager Phil Parkinson said: “I’m delighted to welcome Ryan Hardie to the club.
“We’re looking forward to working with him and I’m sure everyone will give him a warm welcome to the STōK Cae Ras.”
The frontman is keen to continue his goal-scoring form in the upcoming season.
He said: “The last couple of seasons, it’s been good getting experience in the EFL Championship and it’s experience I can lean on now.
“I’ve enjoyed playing there, and I’ve managed to score a few goals, so hopefully that can continue this season.”
