Background: Early surgical results after emergency repairs for the most frequent ventral hernias (epigastric, umbilical, and incisional) are not well described. Thus, the aim of present study was to investigate early results and risk factors for poor 30-day outcome after emergency versus elective repair for ventral hernias. Methods: All patients undergoing epigastric, umbilical, or incisional hernia repair registered in the Danish Hernia Database during the period 1 January 2007 to 31 December 2010 were included in the prospective study. Follow-up was obtained through administrative data from the Danish National Patient Register. Results: In total, 10,041 elective and 935 emergency repairs were included. The risk for 30-day mortality, reoperation, and readmission was significantly higher (by a factor 2-15) after emergency repairs than after elective repairs (p ≤ 0.003). In addition, there were significantly more patients with concomitant bowel resection after emergency repairs than after elective repairs (p < 0.001). Independent risk factors for emergency umbilical/epigastric hernia repair were female gender, older age, hernia defects >2-7 cm, and repair for a primary hernia (vs recurrent hernia) (all p < 0.05). Independent risk factors for emergency incisional hernia repair were female gender, increasing age, and hernia defects ≤7 cm (all p < 0.05). Conclusions: Emergency umbilical/epigastric or incisional hernia repair was beset with up to 15-fold higher mortality, reoperation, and readmission rates than elective repair. Older age, female gender, and umbilical hernia defects between 2 and 7 cm or incisional hernia defects up to 7 cm were important risk factors for emergency repair.