We hypothesized that cardiovascular miRNAs might be diagnostic biomarkers for Kawasaki disease (KD). We identified dysregulated miRNAs in KD coronary arteries, and tested sera from KD patients and febrile controls for cardiovascular miRNAs using 2 methods. We did not identify cardiovascular miRNAs diagnostic for KD; our results may help guide future studies of potential miRNA biomarkers for KD.