The BMA is worried the website will be a popularity contest
Patients in England will be able to comment on their GP's performance on an NHS website, under government plans.
It is hoped the website would improve standards through competition, with people being invited to post messages about their experiences of GPs.
The Department of Health said remarks will be moderated to prevent defamation and the identification or rating of individual doctors.
But doctors' representatives dismissed the idea as a popularity contest.
Health minister Ben Bradshaw said he hopes the consumer feedback will work for healthcare in a similar way to Trip Adviser for the travel industry or Amazon for the book trade.
I think this has everything to do with consumerism and it has not been thought through well
The GP information-sharing scheme will follow the introduction of patient comments about hospitals on NHS Choices last April.
A Department of Health spokesman said it was hoped patients would be able to submit details about doctors' surgeries "by the end of the summer".
"NHS Choices provides a new way of communicating for the NHS, with an open dialogue between the patient, public and services," he said.
"We are encouraging hospitals, and will do so with GP practices, to make the most of the patient comments facility to engage with patients.
"We have seen that the comments are mixed and balanced and this is an opportunity to respond online and demonstrate to prospective and current patients how they (the NHS) are taking feedback on board.
"This will drive improvement. Services will not want their local communities to read negative feedback."
Mr Bradshaw told the Guardian: "I would never think of going on holiday without cross-referencing at least two guide books and using Trip Adviser.
Ben Bradshaw wants the website to spark an Amazon style revolution
"We need to do something similar for the modern generation in healthcare.
"I can already learn a lot from the comments of people, both positive and negative, about a type of treatment or a hospital. We need to extend the service to cover GPs."
The British Medical Association accused the government of not thinking the plan through properly and allowing consumerism to come first.
Laurence Buckman, chairman of the BMA's GPs committee, said: "A website on which people can slander or praise irresponsibly is the wrong approach.
"Patients should be able to choose a doctor, but I don't think this is the way to do it."
Comparing it to Strictly Come Dancing by tempting GPs to encourage patients to "vote" for them, he added: "I think this has everything to do with consumerism and it has not been thought through well.
"I am happy for people to praise or criticise their doctor, but this is not the way professionals should interact with their patients.
"It has a great potential to be misleading."