"That's really been the focus. That's what everyone should be focused on. That's our scorecard," he said in a "Squawk Box" interview.
"We are well on our way to 3 percent or higher sustained growth," he predicted.
The Commerce Department reported last month that U.S. economic growth slowed in the first quarter, advancing at a 2.3 percent annual rate. However, GDP in the first three months of the year tends to be sluggish because of seasonal quirks.
Mnuchin said the stock market is reflecting an improving economy, adding he is "very bullish on stocks."
"There have obviously been various different world events and things that have created some volatility," he said. "But the stock market is up an enormous amount since the election."
Since the 2016 election, as of Friday's close, the Dow Jones industrial average was up more than 34 percent; the was up over 26 percent; and the was up more than 41 percent.
In early Monday trading, the Dow was rising about 350 points, or 1.4 percent, eclipsing 25,000 for the first time since mid-March. The S&P and Nasdaq were up around 1 percent.
Wall Street drew strength from Mnuchin's comments on Sunday that the U.S.-China trade war was "on hold" after negotiators setting up a framework for further discussions.
Monday on CNBC, the Treasury secretary said, "We've made very meaningful progress."
"You combine this with tax cuts, and I think we're looking at very strong GDP growth for the rest of the year," he told CNBC's "Squawk Box."
Mnuchin had previously said the Trump administration's long-term economic growth outlook of 3 percent would pay for the corporate tax cuts and individual tax reforms that Congress passed in December and the president signed into law.