Returns for Kuwait's sovereign fund, the Future Generations Fund, grew 33% in the year to March 31, the finance ministry said on Twitter.
The fund is managed by the Kuwait Investment Authority (KIA), which had more than $580 billion in foreign assets at the end of last year, according to ratings agency Fitch.
A government source told Reuters the bull run in US stocks was one of the main drivers of the rise in the FGF's returns, which increased by more than $150 billion in the last fiscal year.
"We are overweight in the United States and we are overweight in US stocks - more than 50% of our assets were stocks. This was very good for us," the source said.
"At the beginning of the fiscal year the markets were down significantly, and we started at a low base. We had cash and it was used to buy assets in markets that were up 50% in the last fiscal year."
Kuwait's fiscal year runs from April 1 to March 31.
