给根棒槌认作针

Traditional (Taiwan): 給根棒槌認作針

gěigēnbàngchuirènzuòzhēn ㄍㄟˇ ㄍㄣ ㄅㄤˋ ˙ㄔㄨㄟ ㄖㄣˋ ㄗㄨㄛˋ ㄓㄣ

    • to be so gullible as to take something fake for the real thing

Character by character

Saying俗语俗語

Idiom惯用语 · Rarely used now

Literally
given a wooden club, takes it for a needle
Meaning
Describes someone so gullible that they take something fake for the real thing. It is mocking.
Wordplay
针 (zhēn, needle) puns on 真 (zhēn, real): taking the club for a needle is taking it for real.

Sources