The movement calls for an end to the Special Anti-Robbery Squad (SARS), a controversial unit of the Nigerian police force, which human rights groups have blamed for widespread abuses, including torture and killings.
Earlier this month British-Nigerian Hollywood actor John Boyega voiced his support for the campaign, as did popular Nigerian musicians Davido and DJ Cuppy.
A statement from Beyonce on the Twitter feed of her charitable foundation BeyGood, said: “I am heartbroken to see the senseless brutality taking place in Nigeria. There has be to be an end to SARS.
“We have been working on partnerships with youth organisations to support those protesting for change. We are collaborating with coalitions to provide emergency healthcare, food, and shelter.
“To our Nigerian sisters and brothers, we stand with you.”
The protests began two weeks ago after a video circulated showing a man being beaten, apparently by police officers from the squad.
Protests have been taking place across Nigeria, including in major cities Lagos, Abuja and Ibadan.
The unit was disbanded on October 11 but the protests have continued and at least two people were shot on Tuesday.
However, local media reports say that up to 12 people have been killed and others wounded after soldiers opened fire during protests. Amnesty International has said it had obtained credible reports of deaths.
The shootings are said to have taken place after a small group of protesters in Lagos defied a 24-hour curfew that has been put in place in response to the protests.
Beyonce's response comes days after Nigerian singer Tiwa Savage, who worked with Beyonce on her visual album Black Is King, called on her and her team to use their voices and platforms to raise awareness about the situation in the country.
She said: "We need support, it’s gone on for years, we need support.
"I want to use my platform right now to call Beyonce and the whole team that reached out to a lot of Nigerians, Nigerian artists, producers, video directors, dancers, creatives.
"I want them to please use their voice and their platform right now because this same country that birthed this genre is on fire right now. It is on fire.
"I’m calling on Beyonce and the whole team and I am telling you you can’t ignore this, you cannot be quiet."
World heavyweight champion Anthony Joshua said he plans to visit family and friends in Nigeria after training in December and plans to give "tangible" support to the campaign.
In a video shared on Twitter, Joshua said: "Myself, I have had to take time to understand the issues that people in Nigeria are facing. And why sometimes I'm silent is because I've learnt that my silence can't be misquoted.
"Me and my family and my close friends have been trying to do some tangible things and we're organising many, many care packages for people on the grounds."
He said he plans to meet Nigerians who "are making long-lasting change" adding: "Your voices have definitely landed on my ears and you definitely have my support."
Lagos-born Manchester United footballer Odion Ighalo spoke out about the #EndSARS after his team's Champions League win on Tuesday evening.
The striker said: "I am sad and I am broken right now. I'm not the kind of guy that talks about politics but I can't keep quiet anymore about what is going on back home in Nigeria."
"I will say to the Nigerian government, you guys are the shame to the world for killing your own citizens, sending military to the streets, to kill unarmed protestors."
He added: "This Government are killers and they will keep killing if we do not talk about this."
A petition urging the UK Government to sanction the Nigerian government over human rights violations and abuses has already attracted over 150,000 signatures.
This means the issue will be scheduled for debate in parliament.
Nigeria's President Muhammadu Buhari has not made a statement in relation to the shootings but has called on people to have patience as police reforms "gather pace".
Meanwhile, the Nigerian army has confirmed that protestors were wounded but claimed reports of deaths was "fake news".
Lagos state governor Babajide Sanwo-Olu said 25 people had been wounded in what he described as an "unfortunate shooting incident".
In a post on Twitter, he said "forces beyond our direct control have moved to make dark notes in our history" and added that an investigation had been opened into the incident.
"As the Governor of our state, I recognize the buck stops at my table and I will work with the (Federal Government) to get to the root of this unfortunate incident and stabilise all security operations to protect the lives of our residents," he said.
He added that one person was killed due to a "blunt force trauma to the head" in what he said was an "isolated case".
"It is an unfortunate and very sad loss," Mr Sanwo-Olu said. "We are still investigating if he was a protester."