This article aims to develop Avoidant Personality Organization Scale (AVPOS) by using Diagnostic criteria for Avoidant Personality Disorder in Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) as a basis and framework, integrating Kernberg’s Personality Organization theory, fully combining literature review and clinical experience, and investigating its reliability and validity. Sample 1 of 728 people (197 males and 531 females, average age 26.34±8.37 years) filled out the basic information questionnaire, Millon Clinical Multiaxial Inventory (MCMI) avoidance scale, and the initial version of AVPOS questionnaire to test the validity of the association between AVPOS and MCMI. Sample 2 of 709 people (160 males, 549 females, average age 19.34±1.23 years) filled out the basic information questionnaire, IPO, and the initial version of AVPOS questionnaire to test the validity of the association between AVPOS and IPO. Sample 3 of 65 people (13 males, 52 females) from sample 2 filled out the AVPOS again one month later to test the retest reliability of AVPOS. Sample 4 of 743 people (male 182, female 561, average age 22.76±6.86 years), from the half of the total sample (Sample 1 plus Sample 2), were used for exploratory factor analysis. Sample 5 of 694 (176 males, 518 females, average age 22.81±6.97 years), from the other half of the total sample, were used for confirmatory factor analysis. The results of factor analysis showed that the four-factor model was the best factor model for the AVPOS. The AVPOS was positively correlated with MCMI-III (r = 0.658, p<0.01) and IPO (r = 0.328, p<0.01). The AVPOS’s internal consistency coefficient was 0.786; the test-retest reliability of the total scale is 0.841. The results showed that the AVPOS meets the psychometric requirements.