That would mark a sharp pick-up from 2011, when the export-reliant economy is estimated to have expanded by 1.5 percent, according to the government's National Economic and Social Development Board.
"The government targeted the country's economic growth at five percent this year," Yingluck told an economic forum.
She said Thailand aimed to reduce its dependence on the United States and Europe as export destinations, in favour of emerging markets such as the Middle East, India and the rest of Southeast Asia.
"Now time is running out. Other countries have highly competitive economies, while Thailand was recently affected by the massive floods," Yingluck said.
"I believe that the government's economic policy will bring about a V-shape recovery, and we will see better signs from the second quarter."
Many factories in Thailand's industrial heartland have been closed for months because of the damage caused by last year's floods.
Japanese auto giant Honda has idled operations since early October at its factory in Ayutthaya and expects to restart the plant from late March.
Thailand's central bank in January cut its benchmark interest rate for the second time in three months, to 3.00 percent, in a bid to stimulate the weakened economy.
The government said Wednesday that inflation slowed to an annual rate of 3.38 percent in January, from 3.53 percent in December.