Objective-To evaluate associations of serum C-reactive protein (CRP) concentration with duration of hospitalization and with outcome in puppies with canine parvoviral enteritis. Design-Prospective observational study. Animals-79 client-owned puppies with naturally acquired canine parvovirus infection. Procedures-All puppies received supportive care. Serum CRP concentration was measured at the time of admission, approximately every 10 to 12 hours for the first 48 hours, and then every 24 hours until discharge from the hospital or death. Associations between outcome and CRP concentration at various time points or changes in CRP concentration over time were assessed via multiple logistic regression. Associations of CRP concentration with survival time and duration of hospitalization among survivors were estimated with Cox proportional hazards regression. Use of CRP concentration to predict outcome was evaluated by means of receiver operating characteristic curve analysis. Results-Serum CRP concentrations at admission and 12 and 24 hours later were positively associated with odds of death, and CRP concentrations at 12 and 24 hours after admission were negatively associated with survival time for puppies. Among survivors, duration of hospitalization was positively associated with CRP concentrations at 12, 24, and 36 hours after admission. Sensitivity and specificity of CRP concentration to differentiate between survivors and nonsurvivors at 24 hours after admission were 86.7% and 78.7%, respectively (considered moderately accurate). Conclusions and Clinical Relevance-Although serum CRP concentration was associated with outcome in puppies with canine parvovirus enteritis, it did not prove to be a good predictor of outcome when used alone.