Objective The value of echocardiography for the diagnosis and differential diagnosis of children with EFE and the children of MCLS in kawasaki disease was studied， which provided a theoretical basis for the specific use and disease analysis of the clinical assistant examination method. Methods During January 2014 - December 2016， 1756 cases of kawasaki disease in our hospital， 1032 cases of endocardial elastic fiber hyperplasia patients， 1340 cases of medical center residents health study， comparing three sets of objects， echocardiography results of clinical symptoms constitute （LA， RV， LVDd， LVEF， LVFS， E/A） of the differences between each other， analysis of EFE and MCLS children before and after treatment， ultrasonic cardiogram statistical differences of the various test results. Results Hyperplasia group and the group of children with kawasaki disease symptoms （respiratory tract infection， fever/sweat， shortness of breath/purple purple， fatigue， crying， be agitated， don''t eat/body weight increased slowly， liver， tachycardia/low heart sounds blunt， heart failure） constitute the differences were statistically significant （P < 0.05）， including hyperplasia incidence （84.97%） and children with kawasaki disease incidence （75.58%） is the most important clinical symptoms were respiratory tract infection；Three groups of echocardiography to detect objects （LA， RV， LVDd， LVEF， LVFS， E/A） result of the difference was statistically significant （both P < 0.05）， specific and compared between two groups， hyperplasia group and healthy group between， between kawasaki disease group and healthy group， hyperplasia and kawasaki disease group， the difference of each index showed significant （P < 0.05）；Endocardial elastic fiber hyperplasia disease patients before and after the comparison of testing results of echocardiography， LA， RV， LVDd， LVEF， LVFS， E/A show the differences were statistically significant （P < 0.05）， the concrete analysis of each index difference sources， both for the group factor， time factor and the influence of the interaction between （P< 0.05）. Conclusions Echocardiography for endocardial elastic fiber hyperplasia children， children with kawasaki disease， diagnosis and differential diagnosis of normal infants have significant guiding role， at the same time the specific detection of parameters can be used in the endocardial elastic fiber hyperplasia and children with kawasaki disease outcome of the process of evaluation.