He said he was proud everything he and the sport and recreation team had been working towards was covered in the Long-term Plan and Annual Plan.
He said there would be more to say at the council's final meeting of the term in August.
Mayor Steve Chadwick said the council and communtiy would understand Sturt's decision.
"You have done so much about the little things that make a huge difference.
"I congratulate you personally but health matters more."
Sturt said while his ongoing battle with cancer was a factor, his decision was more based around the fact he felt he had achieved everything he had wanted.
"All of my goals are in the Long-term Plan and have been budgeted for."
Sturt survived prostate cancer in 2013 but the disease returned last year in his kidney.
In October last year, he broke his silence about his cancer struggle through the Rotorua Daily Post, revealing he had been told he had months to live but had "won the fight of his life" and had then been given a clean bill of health.
While some tumours had now reappeared, Sturt said his health was being managed well by doctors and it was possible he would live for years.
However, he said he had a change of heart regarding his future on the council and said he would instead step down to allow new blood to come through.
He said he hoped any new councillor taking his place would continue with the "positivity" and "growth the city was currently seeing".
Sturt's local body career started when he was elected as a Ngongotahā County Borough Council member in 1982.
He first became a district councillor in 1989 and has served for 30 years, apart from a short break in the 1990s when he resigned to care for his wife, Denise, who nearly died in childbirth. That bi-election was won by current mayor Steve Chadwick.
Chadwick said her and Sturt went back a long way, having being West Ward councillors together.
She described Sturt as "loyal and passionate" about the people he valued and represented.
"Over the years we have had our differences, but I so respect his advocacy on issues that make a difference in people's lives.
"He is a wily fox of a politician who knew what worked and what wouldn't. He knew every trick in the book."
She said he would now enjoy the love of his family and keep a watching eye on the next generation of politicians.
"Thirty years of public life is a remarkable contribution. Thank you Charles and Denise who walks beside him."
# Read more: A full exclusive interview with Charles Sturt where he reveals details about his health and names newbies he hopes will fill his shoes will be available on this website later today.