Councillor Gurmukh "Mak" Singh, who has represented the Spring Vale ward for five years, said he joined the Labour Party due to it representing "the ordinary person".
But now he said the "values and beliefs" which led him to join had "faded away" from the party as he criticised the leadership of Keir Starmer.
It is the second time a Labour councillor has defected to the Tories in the city in recent years after Payal Bedi-Chadha, who has since stepped down, did so in 2019.
Councillor Singh, who was first elected in 2016 and comfortably defeated the Tory candidate in his ward in May, said: "I realise that my announcement will come as a surprise to many. In these unprecedented times, it is not able being on the left, right, or centre; it is about getting outcomes for local people.
"I know that many residents agree with me and I am grateful to those who told me, at the recent elections, that they were voting for me on a personal level.
"I joined the Labour Party thinking that I would be part of a political party that was there for the ordinary person on the street. Over the years, I have felt that the values and beliefs which aligned with mine have faded away from the Labour Party.
"I have felt this especially in the last year, where Keir Starmer has spent his time finding faults in the response to Covid-19. We are all in this together, and the Prime Minister Boris Johnson has put the people of this nation first. For me, it is all about adding value to our city and I believe that only the Conservatives can do this."
The decision means the Conservatives now have 16 councillors on Wolverhampton Council, with Labour still in firm control with 43 and there being one independent councillor.
Councillor Singh added: "I am just as dedicated to serving my residents, as someone who lives locally and is known to many as a community man and close friend. This was a difficult decision, but I passionately believe that it was the right one. I hope that people will judge me on my record - past, present, and future. I look forward to working in harmony with everyone to build on this."
Stuart Anderson, MP for Wolverhampton South West, said: "Councillor Gurmukh Singh has proudly served the great people of Spring Vale and beyond for the last five years. He is a well-known and respected member of the community.
"I am delighted that Mak is joining Conservative Group as we deliver on our agenda to level up opportunities for local people and unleash our city’s potential. Wolverhampton has been left behind for many years. Working with like-minded community driven activists such as Mak, we are determined to see this change."
Councillor Wendy Thompson, leader of the opposition Conservative Group in the city, said she "wholeheartedly" welcomed him to the Tories.
She added: "Mak has seen the hard-work and dedication of our Conservative councillors and MPs and has made the independent decision to join us as we invest in local priorities – creating jobs, investing in the NHS and our schools, and making our streets safer for all."
Pat McFadden, the Labour MP for Wolverhampton South East, said: "There have been defections before in politics but to do it within a few weeks of being re-elected as a Labour candidate is not the way to treat the voters.
"The people in Spring Vale ward deserve better from someone who sought and won their support only last month as a Labour candidate."