Objectives: The purpose of this paper was to validate the Korean version of the Commitment Inventory (CI), originally constructed and validated by Stanley and Markman (1992). Method: The data for analysis were collected from adults who were in romantic relationships such as dating, cohabiting, or married. There were 328 adults included in the exploratory factor analysis and 336 in the confirmatory factor analysis. Results: The result from the exploratory and confirmatory factor analyses produced an 8-factor model, which included the following factors: “personal dedication,” “social pressure,” “divorce morality,” “child welfare concern,” “procedure difficulty,” “guilt for leaving,” and “alternative availability.” Criterion validity was confirmed with the significant correlations and with the measures included in the study, including the “Investment Model Scale,” the “Marital Satisfaction Inventory,” and the “Relationship Assessment Scale.” Conclusion: Implications and suggestions for future studies were discussed.