Abstract: Objective: To investigate ICU nurses' knowledge, attitudes, and practices on pain, agitation, and delirium (PAD). Methods: A convenience sampling method was implemented. The questionnaire composed of demographics data, questions related to knowledge, attitudes, and practices on PAD. Results: Totally 252 nurses from 28 hospitals were included. The score of ICU nurses' knowledge, attitudes, and practices on PAD was 28.67±8.00, 40.10±5.59, and 27.15±9.22 respectively. Multiple regression analysis showed PAD training, knowledge and hospital's level were the influencing factors of practice. Conclusions: ICU nurses' knowledges on PAD are insufficient. Their attitudes are positive. Their practices need to be improved. Training on PAD management are suggested to enhance clinical outcomes.