But a surge of "likes" from countries including the Philippines has reignited allegations that his digital adoration is purchased from so-called "click farms".
The 64-year-old prime minister, a once self-confessed tech dinosaur who tolerates little dissent, has embraced Facebook with gusto in the last year after opponents used the platform to reach out to younger voters.
He has vowed to remain prime minister until he is 74 with the next elections due in 2018.
With loyalists controlling nearly all of Cambodia's mainstream media outlets, Hun Sen was initially wary of social media.
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But in the last year he has embraced the digital sphere -- while ramping up prosecutions against people for online comments.
His slick page now documents everything from live broadcasts of speeches and meetings with villagers, to more personal moments like the premier kicking back in a white bathrobe or sporting a wet, see-through singlet at the beach.
In recent months, opposition groups, local media, analysts and even many of Hun Sen's own Facebook followers have all remarked on the unusual and erratic surges in likes his page receives.
An AFP analysis of Hun Sen's Facebook followers over the last six months using data from SocialBakers.Com shows two periods when overseas likes have dramatically spiked -- the most recent in the last three weeks.
Only 55 per cent of Hun Sen's five million Facebook followers now come from inside Cambodia.
In contrast, 82 per cent of followers for Sam Rainsy -- the country's most prominent opposition politician -- are Cambodian.
That has led Rainsy, who currently lives in self-exile in France, to accuse Hun Sen of buying friends.
India now accounts for the largest chunk of overseas love for Hun Sen's page -- some 562,000 fans, or 11.4 percent, dwarfing even neighbouring Thailand where there is a huge diaspora of Cambodian workers. In March and April, Indian likes tripled from 175,000 to 517,000.