He also criticized the gifts he said she accepted from foreign donors, and the email scandal that has haunted the Democrat's campaign. He said foreign actors "totally own her."
In his nationally televised comments at the Trump SoHo hotel in New York, he focused on Clinton's foreign policy, as well as her trade and immigration policies, and offered an alternative — if vague and rambling — set of reforms.
"We'll stand up to countries that cheat on trade," Trump said, adding that he'll lift restrictions on energy production and rules that send jobs abroad. He also lambasted Obamacare, vowing to repeal and replace it, calling it "a total disaster." He also said he would increase available technology for the military, rebuild inner cities and infrastructure, and create jobs.
"Hillary's massive taxation, regulation, and open borders will destroy jobs," he said. "Our country is going to start working again."
The remarks came as Trump seeks to pivot toward the general election and quiet a growing wave of criticism — from Democrats and Republicans — that he does not have the temperament or campaign to win the presidency.
Trump's salvo came a day after Clinton tore into Trump's business record.
"Every day we see how reckless and careless Trump is. He's proud of it," Clinton said in Columbus, Ohio. "He's written a lot of books about business. They all seem to end at Chapter 11."
Trump's speech had originally been planned for last week, but he pushed it back after the mass shooting in an Orlando, Florida, nightclub.
On Monday, he fired campaign manager Corey Lewandowski. Hours later, a top campaign aide resigned. On Tuesday, Trump made headlines for a dismal May fundraising report that revealed an extremely low war chest, especially compared with Clinton.
Republicans have expressed optimism that Lewandowski's departure marked a turning point for Trump's campaign. The candidate has also begun to ramp up his fundraising for the general election, holding an event in New York City on Tuesday evening co-hosted by several high-profile financiers, including John Paulson.