The book topped a poll to find the weirdest-ever winner of Britain's Diagram Prize for unusually monickered volumes.
It beat previous winners including "Proceedings of the Second International Workshop on Nude Mice" and "How Green Were the Nazis?" in an online vote. The results were announced Friday by trade magazine The Bookseller, which organizes the prize.
The runner-up was "People Who Don't Know They're Dead." Third place went to "How To Avoid Huge Ships."
The Bookseller's charts editor, Philip Stone, said - possibly with tongue in cheek - that the winning book may have benefited from Britons' concern about the closure of rural post offices across the country.
"I sincerely believe that this title provides further proof to the current government that the British public are passionate about the maintenance and continuation of local mail delivery services," he said. "And not just nationally, but internationally."
Rules for the prize, launched in 1978, say the books must be serious and their titles not merely a gimmick. "Greek Rural Postmen" was published in 1994 by a British stamp-collecting organization.
Its co-author, Derek Willan, said he didn't consider the title odd.
"It purely describes what's in the book," Willan, 91, told the British Broadcasting Corp. "This book was issued by the Hellenic Philatelic Society of Great Britain and it is of interest to Greek philatelists."