This paper presents the development and psychometric properties of an interpersonal problem-solving inventory for Vietnamese elementary school students (IPSI). The IPSI consists of five subscales: Positive problem-solving behavior; Negative problem-solving behavior; Rational problem-solving behavior; Impulsive behavior; and Avoidance behavior. The scale was administered to a total sample that consists of 730 Vietnamese fifth grade students (age 10-14, M = 10.70, SD = 0.56). Multiple psychometric analyses were utilized including classical test theory (CTT), exploratory factor analysis (EFA), and confirmatory factor analysis (CFA). Reliability of IPSI was reported by calculating internal consistency. Findings showed that the IPSI has adequate internal consistency (Cronbach's [alpha] = 0.90; McDonald's [omega] = 0.82). The EFA findings suggested that the IPSI has two-factor structure. The CFA findings indicated that the IPSI has the theory-driven five-factor structure that has the adequate fitness indices (X[superscript 2]/df = 1.369, p < 0.001; GFI: 0.930; TLI: 0.926; CFI: 0.871; RMSEA: 0.032; SRMR: 0.046). These findings suggest that the IPSI is a well-functioning scale with good psychometric properties. Recommendations and weak points of the scale are discussed. Future research and possible improvements are proposed.