The brother of Stephen Lawrence has complained to the Metropolitan Police claiming officers stopped and searched him because he was black.
Stuart Lawrence's lawyer said the complaint related to an incident on 16 November but the teacher had faced "harassment" for years.
The Met said the complaint was "a very serious matter and it will be investigated thoroughly and speedily".
In 1993, Stephen Lawrence was murdered in a racist attack in Eltham.
Last year Gary Dobson and David Norris were convicted of the 18-year-old's murder in south-east London.
The Metropolitan Police faced criticism over the original investigation into the death and a public inquiry branded the force institutionally racist.
Stuart Lawrence, 35, told the Daily Mail he had been stopped by police up to 25 times over several years.
His solicitor Imran Khan said Mr Lawrence decided to formally complain after he was halted by police on 16 November.
Mr Khan said: "That was the straw that broke the camel's back.
"That was the culmination of a course of conduct over many years which amounted to harassment and discrimination based upon his skin colour, his ethnic origin."
Hoping that the issue would be resolved out of court, the lawyer added: "We are delighted that they (Scotland Yard) are pursuing it so quickly."
Lawrence experience 'not unusual'
A statement from the Met said: "Mr Lawrence's complaint, which we received last night, is a very serious matter and it will be investigated thoroughly and speedily.
"Stop and search is an important tool to combat crime and is supported by the community if it is used professionally and fairly.
"Officers are accountable for their actions and it is therefore essential complaints such as these are fully investigated.
"The Commissioner has made it clear that he will not tolerate any form of racism. Strong action will be taken against any individuals if they are found to have acted in a racist manner."
James Welch, legal director for human rights group Liberty, criticised the power of stop and search saying: "Statistics suggest that Mr Lawrence's experience of repeated searches is not unusual.
"The police maintain that stop and search is an important tool in their armoury. But they seem incapable of exercising the power in a non-discriminatory way."