Biden's visit to the city came amid pressure to protect voting rights in states that have passed or are considering laws to restrict voting after Georgia, Texas and Florida have already passed such laws.
The laws appear to be a response to Trump's debunked and false claims of rampant voting fraud in the presidential election last fall.
Biden said federal judges have thrown out dozens of court challenges, including some appointed by Trump, and Wisconsin, Arizona and Georgia confirmed his win through audits and recounts, including three recounts in Georgia alone.
"It's clear, for those who challenge the results or question the integrity of the election, no other election has ever been held under such scrutiny or such high standards," Biden said at the National Constitution Center. "The big lie is just that, a big lie."
Hours before Biden spoke, Trump issued a statement calling for Pennsylvania to conduct an audit of the 2020 results in the state, which Biden won by roughly 80,000 votes, The Hill reported.
"In America, if you lose, you accept the results," Biden said in his Philadelphia address. "You follow the Constitution, you try again. You don't call facts 'fake' and then try to bring down the American experiment just because you're unhappy. That's not statesmanship. That's selfishness."
In his remarks, Biden equated the new laws, enacted mostly by Republican-controlled Southern states, to past discriminatory voting laws like poll taxes, literacy tests and voter intimidation tactics by groups such as the Ku Klux Klan.
"The 21st Century Jim Crow assault is real, it's unrelenting, and we're going to challenge it vigorously," Biden said. "While this broad assault on voting rights is not unprecedented it is taking on new and pernicious forms."
Attorney General Merrick Garland has announced that "the United States Department of Justice is going to be using its authority to challenge the onslaught of state laws undermining voting rights in old and new ways," Biden said during his speech.
White House Press Secretary Jen Psaki told reporters Monday that the voting law changes have been driven by Trump's repeated false claims, which he continues to make at every public appearance.
"He will call out the greatest irony of the 'big lie' is that no election in our history has met such a high standard with over 80 judges, including those appointed by his predecessor, throwing out all challenges," Psaki said, according to ABC News.
Biden's speech also came as Democratic lawmakers in Texas fled the state for a second time to deny the Republican-led state Legislature the quorum it needs to pass new laws that would limit voting there.
According to the Brennan Center for Justice, 17 states have enacted 28 new laws that restrict voting access.
"There's an unfolding assault taking place in America today in attempt to suppress and subvert the right to vote in fair and free elections, an assault on democracy, an assault on liberty, an assault on...who we are as Americans," Biden said.
"Bullies and merchants of fear, peddlers of lies, are threatening the very foundation of our country, it gives me no pleasure to say this. I never thought in my entire career I'd ever have to say it.
"But I swore an oath to you, to God, to preserve, protect and defend the Constitution, and that's an oath that forms a sacred trust to defend America against all threats both foreign and domestic."
Biden ended his speech by citing the late civil rights icon, John Lewis, who once said: "Freedom is not a state, it's an act," while urging people to unite and take action to protect voting rights.