This study examined factors impacting the big data adoption of small and medium enterprises (SMEs) in Vietnam. The mixed method study was used. The qualitative research was applied by a group discussion with 15 participants and a cross-sectional survey with 372 representatives of SMEs. The results show that perceived benefit, simplicity, compatibility, data quality, security and privacy, vendor support, management support, financial investment, perceived usefulness, and attitudes toward adoption. This research extended the academic framework and examined causal relationships by adopting new characteristics from the integrated perspective of TOE with TAM beyond the existing research models.