Simpson died Thursday in Chicago after a year-long battle with brain cancer, Tennis Canada said in a statement.
"We are extremely saddened and carry a heavy heart by the news of Rene's passing," said Hatem McDadi, Tennis Canada's vice-president of tennis development. "We have lost a very dear friend and member of our tennis family. Rene will be remembered for her courage, patriotic spirit, warmth and loyalty to friends and family. She has been an inspiration and a role model to friends, family and our current generation of female tennis players.
"Rene is dearly loved and will be missed. We extend our deepest condolences to Rene's family and friends including her husband Jason Collins, her parents Burt and Jane and her sisters Carol and Anne. Our thoughts and prayers are with them during this difficult time."
As a player, Simpson made her first Grand Slam appearance at the Australian Open in 1989. She reached a career high of No. 70 in April of that year and advanced to the third round at the French Open.
In doubles, she was ranked as high as No. 32, won three titles and was a US Open quarter-finalist. She won three singles tournaments and four doubles titles on the lower-tier ITF circuit.
Simpson was a regular player on Canada's Fed Cup team in the 1990s and recorded a 20-16 record in tournament play. She served as team captain from 2001 to '09 and guided Canada to a World Group II berth in 2007.
WTA chairman and chief executive officer Stacey Allaster, a former Tennis Canada vice-president, issued a statement Thursday.
"Rene was a truly special person who touched the lives of so many in such a positive way," Allaster said. "A great champion on and off the court, she was an inspiration to generations of young Canadian girls who loved the sport of tennis and the competition like she did.
"Rene loved to win and she was incredibly proud of representing Canada on the WTA's world stage, and although she enjoyed a lot of success on the court her greatest accomplishment was living a full life and living the life she wanted to live."
Memorial services will be held at a later date in both Chicago and Toronto.
"Today we are deeply saddened to lose our friend," Allaster said. "And although our WTA star has lost her fierce battle with cancer, her competitive, independent spirit will inspire us and our memories of Rene will continue to shine brightly.
"As a personal friend of Rene, and on behalf of Rene's former competitors and everyone in the WTA family, our hearts go out to her loving and supportive husband Jason, her parents, sisters and friends on this incredibly sad day."
Simpson was inducted into the Canadian Tennis Hall of Fame in 2011. She will be honoured by Tennis Canada during the upcoming World Group II first-round tie Feb. 8-9 against visiting Serbia.