Members of the #OperationShutdown group, including those who have lost family members to knife and gun crime, chanted YouTube-Blood On Their Hands and Drop The Knife, Save A Life as they staged the protest on Friday lunchtime.
Bemused onlookers watched as around 20 women, first outside the King's Cross premises of Google, parent company of YouTube, and then the offices of the video sharing website itself, poured fake blood on their hands and their clothes, and swirled it on the floor outside.
They were then received by Ben McOwen Wilson, the regional director of YouTube UK, who agreed to speak to the campaigners about the issue.
Lucy Martindale, a youth worker from south London and one of the chief organisers, described the talks as a "positive outcome."
"He has acknowledged that there is a problem with violent drill music, that they are trying to work hard to reduce it bu that they are not doing enough and they need to do more," she told the Press Association.
"He has agreed to sit down with us in the next couple of weeks to to see how we can work with YouTube in helping to flag these videos and give intelligence."
The campaigners said they want the social media network giant to take a tougher stance against content which promotes knife crime.
Speaking during the protest, Ms Martindale said: "Knife crime has been a huge part of my life since I was nine years old, I witnessed my cousin being murdered when I was outside playing.
"I grew up surrounded by gangs, within seven years I lost 11 family and friends to murder, gun and knife crime.
"We believe YouTube plays a part in the rising knife crime we see.
"I work with young people and every day they are reciting drill lyrics, talking about what they are going to do. We have approached YouTube several times and asked them to control their content and remove certain videos.
"Why is it taking them seven months to remove one video of men with knives and guns where they were saying 'we're glad your mother buried you and were going to kill your other children?'
"That's not OK."
The 29-year-old mother-of-three young children, added: "It's not just about blaming the police or blaming the mayor, everybody has a part to play, and we just hope by doing these campaigns and raising awareness a small change can be made."
Earlier, the group threatened a sit-down protest outside the entrance to nearby King's Cross St Pancras station after being told to move on by officials.
British Transport Police, who were called by Network Rail after the campaigners refused to leave the station forecourt, later agreed the women could stay for an hour before moving on.
A spokesman for YouTube, which says it blocks videos in the UK where an individual brandishes weapons in a threatening manner, said: "We have developed policies specifically to help tackle videos related to knife crime in the UK and are continuing to work constructively with experts on this issue.
"We work with the Metropolitan Police, the Mayor's Office for Policing and Crime, the Home Office, and community groups to understand this issue and ensure we are able to take action on gang-related content that infringe our community guidelines or break the law.
"We have a dedicated process for the police and the Prison Service to flag videos directly to our teams because we often need specialist context from law enforcement to identify real-life threats.
"Along with others in the UK, we share the deep concern about this issue and do not want our platform used to incite violence."
It comes as figures released last month show knife crime at record levels in England and Wales.
Data from the Office for National Statistics (ONS) showed an increase of 6% in a year and the largest total since comparable data began in 2011.
The ONS release showed an increase in knife offences in 31 of the 43 police forces across the two nations.
The number of violent offences recorded by police was more than 1,608,500 last year - a 19% increase on 2017.
In recent weeks Health Secretary Matt Hancock has held a series of meetings with social media giants in an effort to reduce the amount of harmful content being uploaded to their various platforms, including posts about child abuse, eating disorders and self-harm.
The recent online harms white paper has set out a new statutory duty of care to make companies take more responsibility for the safety of their users and tackle harm caused by content or activity on their services.
Compliance with this duty of care will be overseen and enforced by an independent regulator.