The Southeast Asian country's latest outbreak has accounted for more than 80% of its total infections and more than 90% of deaths and slowed domestic activity.
The stimulus worth 140 billion baht ($4.5 billion), includes cash handouts for low-income people, cash transfers under a co-payment scheme and e-vouchers for spenders.
It is part of a larger economic package worth 255 billion baht approved by the cabinet last month.
"The measures will cover 51 million people and help sustain purchasing power... and support the economy in the second half of 2021," Kulaya Tantitemit, head of the finance ministry's fiscal policy office, told a briefing.
The measures, expected to be implemented from July to December, include 93 billion baht in co-payments for consumer purchases, as well as 28 billion baht of e-vouchers for spending.
Some 16.4 billion baht of cash handouts will be offered to low-income people and 3 billion baht to people with special needs.
Last month, the state planning agency cut its 2021 economic growth outlook to 1.5%-2.5% from 2.5%-3.5% due to the outbreak.
It could take until the first quarter of 2023 for Southeast Asia's second-largest economy to return to pre-COVID-19 levels, longer than previously anticipated, according to Bank of Thailand Governor Sethaput Suthiwartnarueput.
($1 = 31.15 baht)
(Reporting by Orathai Sriring, Kitiphong Thaichareon, Satawasin Staporncharnchai; Editing by Ed Davies)