Objective To validate the translated Chinese version of Pain Assessment in Advanced Dementia Scale (C-PAINAD) for its clinical application in assessing the discomfort level of severely cognitive impaired patients. Methods In developing the C-PAINAD, both clinical and academic experts were engaged in an iterative translation process for ensuring its semantic equivalence with its original language as well as it comprehensibility for clinical application. In establishing C-PAINAD's inter-rater reliability, its applicability for clinical use is further assessed in 11 severely cognitive impaired patients. The assessment tools included C-PAINAD, Discomfort Visual Analog Scale (DVA), and Philadelphia Geriatric Center Affect Rating Scale (PGCAR). Correlations, ANOVA and factor analysis were undertaken to examine the reliability and validity of C-PAINAD. Results The scores of C-PAINAD were not in normal distribution but clustered around Zero. C-PAINAD was positively correlated with DVA and negative affect but mildly and negatively correlated with positive affect. It was able to detect different pain level under different condition. One factor was extracted and the percentage of variance was 51.20%. C-PAINAD was proved to have satisfactory reliability and validity(Cronbach's α=0.66). Conclusions C-PAINAD was a simple, reliable and effective pain assessment instrument for measuring pain level of non-communicative patients like advanced dementia. Further research is deemed necessary to conduct with pre - and post-test of analgesic prescriptions prior to wider clinical application.