Children with chronic conditions may be at risk of increased disruptions in health care following natural disasters such as Hurricane Katrina. The objective of this cross-sectional study was to evaluate differences between children and adolescents with and without chronic conditions immediately following Katrina. Of 531 participants, there were 79.8% younger than 13 years old, 50.5% male, 42.8% African American. Participants with pre-existing conditions (39.4% of the total sample) were more likely than those without to be at the clinic for a non-chronic health condition rather than another problem (43.5 vs. 16.2%), to take asthma medication (37.4 vs. 3.9%), to have asthma worsen (16.3 vs. 1.9%), to miss a visit (49.2 vs. 39.8%), to run out of medications (33.9 vs. 7.9%), to live with flood damage (19.7 vs. 11.3%) or mold (23.6 vs. 15.8%), and to experience disruption in care (58.4 vs. 38.3%) or negative psychological consequences (ranging from 2.5% to 12.9%). While the medical differences are unsurprising, given the groups being compared, the other differences between the groups merit attention from policymakers and health care providers. Children and adolescents with chronic conditions are at increased risk of adverse outcomes following a natural disaster. Providers may be able to reduce negative effects on this population by developing condition-specific preparedness care mechanisms.