"Clearly we hoped for better on immigration, where we worked so hard," she said in an interview marking the win, broadcast late Saturday on the TG1 channel.
"The results are not what we hoped to see. It is certainly a very complex problem, but I'm sure we'll get to the bottom of it."
Meloni's post-fascist Brothers of Italy party was elected largely on a promise to reduce mass migration into Italy.
But the number of people arriving on boats from North Africa has instead surged, with more than 130,000 recorded by the interior ministry so far this year -- up from 70,000 in the same period of 2022.
After 8,500 people arrived on the tiny island of Lampedusa in just three days earlier this month, Meloni demanded the European Union do more to help relieve the pressure.
Brussels agreed to intensify existing efforts, and this week said it would start to release money to Tunisia -- from where many of the boats leave -- under a pact aimed at stemming irregular migration from the country.
'Demagogic and consciously cynical'
But Meloni's main coalition partner, Matteo Salvini of the anti-immigration League party, has been dismissive of EU efforts to manage the surge of arrivals that he dubbed an "act of war".
The deputy premier, who closed Italy's ports to charity migrant rescue ships while in government in 2019, is agitating for a tougher approach.
Since taking office in October, Meloni's government has restricted the activities of the charity rescue ships, which it accuses of encouraging migrants, while vowing to clamp down on people smugglers.
It has also sought to boost repatriation of arrivals ineligible for asylum, including by building new detention centres and extending the time migrants can be held there.
It emerged this week it would also be requiring migrants awaiting a decision on asylum to pay a deposit of 5,000 euros or be sent to a detention centre, prompting accusations the state was charging "protection money".
The centre-left Democratic Party said earlier this week that "on immigration, the Italian right has failed".
"It continues on a path that is demagogic and consciously cynical, but above all totally ineffective both in the respect and safeguarding of human rights, and for the protection of Italy's interests," it said in a note.
