"We must be within the first five in the constructors' championship," declared team boss Franz Tost at the launch of the white and blue AT01 car at Red Bull's Hangar-7 facility in Salzburg.
Honda-powered Toro Rosso finished sixth overall last year, equalling their best ever performance, and have an unchanged lineup of Russian Daniil Kvyat and Frenchman Pierre Gasly.
Both drivers finished on the podium in 2019.
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AlphaTauri is a Red Bull-owned fashion brand established in 2016. The team have raced as Toro Rosso since 2006 when Red Bull took over struggling Minardi.
They have brought through a succession of hungry young talents, including Germany's four times world champion Sebastian Vettel, Australian Daniel Ricciardo and Dutch youngster Max Verstappen.
"I think Scuderia AlphaTauri is a fantastic project, a new adventure," said Gasly.
"There's the end of the story of Toro Rosso for sure, which is quite emotional for me because they gave me my first opportunity in Formula One. But there's a new chapter coming with Scuderia AlphaTauri."
Kvyat added: "It’s a big thing going on here tonight. New name for the team, new livery. Of course, technically, the team is going to continue the evolution from last year."
The new car will hit the track for the first time at Misano in Italy on Saturday, with pre-season testing starting in Barcelona next week.
The name may give some commentators a headache, however, with Alfa Romeo, previously known as Sauber, giving their new car its track debut in Italy on Friday.
The potential for Alpha/Alfa confusion brings back memories of 2011 when there were two teams known as Lotus on the starting grid, each powered by Renault engines.
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