Introduction Haemophilus bacteremia (HB) has historically been a pediatric disease. With the advent of conjugated Haemophilus influenzae type B pediatric vaccination, morbidity and mortality of HB was decreased in both the pediatric and adult populations. To understand the current epidemiology and pathogenicity of HB in adults, we reviewed the medical records of all adult patients with HB at our 577-bed adult hospital from January 1, 2001 to December 31, 2012. Methods We reviewed the medical records of all adult patients (≥16 years of age) with Haemophilus species bacteremia at our institution during the 11-year period from January 1, 2001 to December 31, 2012 and reported the epidemiology, source of infection, comorbid conditions, treatment, and mortality of HB for these patients. Results There were 45 cases of HB during the study period. Thirty-nine cases (86.7%) were caused by H. influenzae and 6 cases (13.3%) were caused by Haemophilus parainfluenzae. There were 21 episodes in women (46.7%) and 24 episodes in men (53.3%). The patients’ ages ranged from 20 to 91 years with a mean of 69.6 years and a median of 70 years. The eighth (11 cases, 24.4%) and ninth (13 cases, 28.9%) decades had the highest occurrence of HB. Pneumonia was by far the most common presentation (31 cases, 68.9%), followed by biliary sepsis (4 cases, 8.9%), and skin and soft tissue infections (3 cases, 6.7%). The most common initial therapy for these patients was either an anti–pneumococcal fluoroquinolone or a combination of ceftriaxone and azithromycin, reflecting our institution’s community-acquired pneumonia treatment protocol and order sets. Six of 43 patients died, for a mortality rate of 13.9%. Conclusions Haemophilus species bacteremia is not uncommon in the adult population, is most commonly caused by H. influenzae (86.6%), is most prevalent in the eighth and ninth decades of life, and has a significant mortality rate (13.3%) despite the uniformly appropriate initial empiric antimicrobial therapy. Pneumonia is the most common presenting manifestation causing 68.9% of all cases of HB in our series.