In April, the FTSE 100 company paid out a record US$7.1bn to shareholders, which included a huge US$4.0bn special dividend following the sale of its stake in the Grasberg copper mine in Indonesia.
Nestlé is traditionally the top dividend payer in the second quarter, but Rio relegated it to second place this time around, ahead of Sberbank of Russia.
French healthcare colossus Sanofi and German insurance group Allianz rounded out the top five.
Record quarter for UK dividends
In total, UK dividends grew by almost 9% year-on-year to a quarterly record US$35.0bn.
The largest contribution to the growth came from the banking sector, largely thanks to Royal Bank of Scotland PLC (LON:RBS), which not only restored its regular dividend, but also set aside another US$1.1bn or so (£900mln) as a special pay-out.
“Strong capital ratios and improving profits are enabling the banks to return more cash to shareholders,” said asset manager Janus Henderson which compiled the list.