With 180 trillion won, or 75 percent of the amount, allocated to South Korea, the conglomerate also vowed to directly hire 40,000 more employees through 2023.
Samsung's latest investment plan is 60 trillion won larger than its previous three-year investment pledge in 2018, reports Yonhap news agency.
Samsung's announcement came 11 days after Lee Jae-yong, the de-facto head of South Korea's largest conglomerate, was paroled. Lee, Samsung Electronics Vice Chairman, had been serving prison time since January following a retrial of a bribery case involving former President Park Geun-hye.
Samsung said its latest investment will be used to foster its strategic businesses, including semiconductors, pharmaceuticals, next-generation communication networks and IT research, though it did not reveal how much money will be spent on each sector.
Its crown jewel, Samsung Electronics, will target early development of advanced nodes and cement its dominance in the memory sector while beefing up its competiveness in the logic chip business.
"For memory, we will continue R&D and infrastructure investment with focus on mid-to-long term demand instead of short-term market changes," it said. "For logic chips, we plan to actively execute our existing investment plan early."
The tech giant previously announced that it will invest 171 trillion won in the logic chip and foundry sectors by 2030 to become the No. 1 player.
Samsung Electronics said that its aggressive investment in the semiconductor business can be called a "survival plan" as rivals move ahead to control the global chip supply chain amid the COVID-19 pandemic.
To help the national economy recover from the Covid-19 impact, Samsung will greatly increase the number of its staff by creating 40,000 jobs over the next three years. As of the first half of the year, Samsung Electronics had 111,683 employees.
Samsung claimed that its massive investment plan will have the effect of creating some 560,000 jobs in the cited period.