5G technology could download an 800-megabyte movie file in one second.
South Korea, already one of the most wired countries on Earth, has announced a 1.6 trillion won ($1.7 billion) plan to roll out a next-generation 5G wireless service fast enough to download full-length films in a second.
The science ministry said it aims to implement the technology within six years.
"We helped fuel national growth with 2G services in the 1990s, 3G in the 2000s and 4G around 2010. Now it is time to take pre-emptive action to develop 5G," the ministry said.
"Countries in Europe, China and the US are making aggressive efforts to develop 5G technology ... and we believe there will be fierce competition in this market in a few years," it said.
Under the roadmap, a trial 5G service will be rolled out in 2017 and a fully commercial service in December 2020.
Priority will be given to developing key features for the new network, including ultra-HD and hologram transmission as well as cutting-edge social networking services.
Related industries will be able to rack up sales of 5G-related devices and infrastructure equipment worth 331 trillion won ($350 billion) from 2020 to 2026, the ministry estimated.
The government hopes to implement the plan with investment and co-operation from operators such as SK Telecom and Korea Telecom as well as handset makers such as Samsung and LG.
It also aims to expand the telecom infrastructure equipment industry, which is relatively weaker than the mighty mobile device sector.
Led by Samsung, the world's top handset maker, South Korea has a leading 30 per cent stake in the global mobile device market.
"But the [telecom] infrastructure equipment industry has only a 4.4 per cent share in the global market, with exports very limited," the ministry said.
Chinese equipment makers including Huawei have expanded their presence in the global market from 12 per cent in 2007 to 26 per cent in 2012.
Huawei announced in November it was looking at a 5G commercial rollout by 2020, with a minimum investment of $US600 million to develop the technology.
Seoul intends to take up to a 20 per cent stake in the world's telecom infrastructure equipment market by 2020, according to the ministry.
South Korea is renowned for being at the forefront of internet technology with broadband speeds that consistently outpace those in Australia, Europe and the United States.
5G technology will allow users to download an 800-megabyte movie file in one second, compared with 40 seconds using 4G, the science ministry said, adding that such speeds would help South Korean firms win overseas deals.
Officials said the new service would also mean people on bullet trains running faster than 500km/h would even be able to access the internet, compared with the limit of 300km/h currently.
"Bullet trains around the world keep getting faster, with some in China running as fast as 500 and 600km/h," said one ministry official who declined to be named.
"If we have the technology to allow fast internet access in these trains, it can open new opportunities for us globally," he said.
Samsung announced in May last year it had successfully tested 5G technology, managing data transmission of more than 1 gigabit per second over a distance of 2 kilometres.
Samsung said it had found a way to harness millimetre-wave bands which have proved to be a sticking point for the mobile industry to date.
The test used 64 antenna elements, which the company said overcame the issue of "unfavourable propagation characteristics" that have prevented data travelling across long distances using the bands.
However, it made clear that the technology would not be available commercially before the end of the decade.
Correction: This article originally cited the South Korean government's claim that the new technology would be 1000 times faster than 4G. This claim could not be verified and has been removed.