An evaporated fuel treating device includes a canister, a first purge passage connected to the canister, a second purge passage connected to a second end of the first purge passage and an intake passage, a purge control valve disposed in the first purge passage, a pulsation detection sensor disposed in the second purge passage, and an electronic control unit configured to execute abnormality detection control that detects abnormality of the second purge passage. The electronic control unit is configured to detect pulsation of a purge gas flowing through the second purge passage, based on an output signal from the pulsation detection sensor when the electronic control unit execute a control that opens and closes the purge control valve, and determine abnormality of the second purge passage, based on the detected pulsation.