She said the details would be announced when the government tabled its policies covering a wide range of political, economic and social aspects in Parliament next Wednesday.
"We have to talk to the tri-partite committee which includes employers on their readiness to implement the policy," she said.
Currently the minimum wage ranges from 170 Baht to 220 Baht (RM17 to RM22) per day depending on the province and the minimum wage of 300 Baht was one of the main election promises made by the Pheu Thai party which leads the current coalition government.
To a question whether the minimum wage would be introduced in Bangkok first before being expanded to other provinces, she said the matter was being discussed currently.
"We need some time to work on the matter with the tri-partite committee," she said.
While employees welcomed the minimum wage, many employers were concerned about its impact to their businesses and some small and medium enterprises (SMEs) feared that they may be forced to shut down their businesses.
Economists also fear that the minimum wage could further escalate the rising cost of living and force investors to relocate their businesses to other countries.
On the minimum wage of 15,000 Baht (RM1,500) for fresh graduate as promised by her party, Yingluck said the government had no problem to implement it in the public sector but depended on the readiness of the private sector to follow suit.
At the moment, a fresh graduate with a bachelor degree enjoys a starting salary of about 9,000 Baht (RM900) in the public sector and about 12,000 Baht (RM1,200) in the private sector.
However, Yingluck did not give the deadline for carrying out the policy.
She said another Pheu Thai's election pledge of cutting the corporate tax to 23 per cent from 30 per cent probably would be introduced starting January next year.
She called on critics to give her government one year to prove its achievements in implementing some of the pledges made during the July 3 general election while some pledges may take some time to be implemented as it involved various laws and technicalities.