A mother whose son was circumcised without her consent said she was "furious" the doctor has only been suspended for a month.
The boy was taken to be circumcised by his Muslim grandmother, and Dr Balvinder Mehat did not check the mother consented to the procedure.
Dr Mehat was investigated by the General Medical Council and admitted the allegation at a misconduct hearing.
However, the tribunal decided he was "no risk to patients".
"It's an absolute joke and I won't trust another doctor ever again," said the boy's mother.
"If I went round and cut his bits off I would be getting years in prison.
"Even if they struck him off it wouldn't have been enough punishment, because he has caused my son so much pain, but such a short suspension is a slap in the face."
Dr Mehat said he would be writing a letter of apology "directly to the patient".
"I am very regretful that the care I provided to the patient did not go well as we had both hoped," he said in a statement to the BBC.
"I have reflected on this incident in detail, endeavouring to learn from this unfortunate case."
Dr Mehat, who has worked at Bakersfield Medical Centre in Nottingham since 1989, was also suspended for a month earlier this year because he had not complied with housing regulations for two properties he rented out.
Human rights lawyer Saimo Chahal QC previously became involved in the circumcision case after police dropped their investigation.
- July 2013 - The boy is circumcised when he is three months old. His mother later contacts social services
- November 2014 - The mother contacts Nottinghamshire Police, who later drop the investigation
- August 2015 - The mother complains to the General Medical Council, which later starts investigating
- May 2017 - Human rights lawyer Saimo Chahal writes to police saying they should review the decision not to prosecute
- June 2017 - Police arrest Dr Balvinder Mehat and the boy's paternal grandparents
- October 2017 - Police visit the mother to inform her the CPS had decided to take no further action
- November 2017 - Saimo Chahal receives written confirmation of the CPS decision and reasons
- September 2019 - Dr Mehat attends a misconduct hearing before the Medical Practitioners Tribunal Service, where he admits circumcising the boy without his mother's consent
The boy's mother said she thought people were "scared to do anything because it's a religious issue".
"It's perverted and it shouldn't be done to kids because they can't consent to it," she said.
"Why aren't the NSPCC looking into it? Why isn't the government looking into it? It's illegal to dock a dog's tail or to circumcise a girl but it's legal to circumcise a boy."
She said her son, who was now six, had suffered a lot of pain and repeated infections.
"It's not just my son that's in pain because of it, it's just me that's willing to speak out against it because I didn't consent to it," she said.
At the misconduct hearing, Dr Mehat's barrister said the incident was an isolated one that had not been repeated since.
The Medical Practitioners Tribunal Service found his actions were a "serious breach" of GMC guidance, and his fitness to practise was impaired by reason of misconduct.
However, it decided there was a "very low risk of repetition" and "no risk to patients" by allowing him to continue working.
Dr Mehat was still working when the BBC phoned his practice on Friday. His suspension would take effect on 16 October, unless an appeal was lodged before then.