Poultry red mites (PRMs), Dermanyssus gallinae , are one of the most harmful ectoparasites of laying hens. Because of their public health impact, safe, effective methods to eradicate PRMs are greatly needed. Carbon dioxide (CO 2 ) was shown to eradicate phytophagous mites; however, there is no evidence that PRMs can be eradicated by CO 2 . Thus, the efficacy of CO 2 , applied by direct-spraying and dry ice-generated exposure, for eradicating PRMs was investigated. Both treatments eradicated > 85% of PRMs within 24 h and 100% of PRMs by 120 h of post-treatment. Therefore, these novel approaches may be useful for eradicating PRMs in clinical settings.