Biden's trip to Selma, in Alabama, on Sunday is aimed at underscoring his commitment to Black voters, who helped propel him to the White House and remain a key constituency going into his expected 2024 re-election bid.
It also comes as his efforts to pass voting rights legislation stall in Congress.
"Selma is a reckoning. The right to vote and to have your vote counted is the threshold of democracy and liberty," Biden said in front of the Edmund Pettus Bridge, where state troopers clubbed and used tear gas against the 1965 voting-rights marchers.
"With it, anything's possible. Without it, without that right, nothing is possible. And this fundamental right remains under assault."
Coverage of the brutality of that day against the marchers, including John Lewis, a Black civil rights activist who went on to become a US congressman, shocked the nation and helped spark the 1965 Voting Rights Act.
Biden said votes needed to be found to pass the Freedom to Vote Act and the John Lewis Voting Rights Advancement Act, bills that would make Election Day a holiday, register new voters and strengthen US Justice Department oversight of local election jurisdictions with a history of discrimination.
Republicans, who control the US House of Representatives, oppose the measures.
The president, who has said he intends to run for re-election, has sought to buttress his support from African American voters.
Last month, the Democratic National Committee approved a shake up of the party's 2024 primary calendar, making South Carolina - a state with a high percentage of Black voters - first in line for holding its presidential nominating contest, displacing Iowa.
In January, Biden spoke at the Atlanta church of slain civil rights leader Martin Luther King Jr.
Biden's visit to Selma follows Vice President Kamala Harris's trip there last year for the anniversary of the march.
"If we are to truly honour the legacy of those who marched in Selma on Bloody Sunday, we must continue to fight to secure and safeguard the freedom to vote," Harris said in a statement on Sunday.
Then-president Barack Obama spoke at the 50th anniversary of the march in 2015 and walked across the bridge with his wife, Michelle, and Republican former president George W Bush and his wife, Laura.
