Transthoracic echocardiography (TTE) has brought a revolution in pediatric cardiology. The aim of this study is to evaluate the validity of non-invasive diagnostics in relation to invasive, and its ability to define morphology and haemodynamics of congenital heart disease (CHD). During September 1966 till April 2001 at the Cardiology department of the Paediatric Clinic in Sarajevo, a group of 90 pts were evaluated with diagnosed CHD (54% boys). Diagnosis of CHD, except clinical examination, ECG and X ray has been confirmed by ultrasound (US) on a "Hewlett Packard" and "Toshiba" SSH165, using 5 MHz and 2,5 MHz Doppler. CHD-s type L-R shunt have been diagnosed in 37 pts (41,2%), obstructive in 19 (21,1%) and cyanotic in 34 pts (37,7%). According to US findings, surgical correction has been suggested and performed in 77 pts; abroad in 89,6% (69 pts), and in 10,4% (8/77) in Sarajevo. In 44/90 (48,8%) cardiac catheterisation was done; in 29/44 as diagnostical and in 15/44 as therapeutical tool. 61/90 pts (67,8%) had diagnosis done only by US, and by diagnostic catheterisation it was completed in 19/90 (32,2%). 46/77 operated pts (69,7%) had diagnosis done by US; in 30 pts (67,3%) as a simple CHD and as complex CHD in 16 (32,7%). By comparasion of US findings and findings from the operating table, the correct US findings have been in 68/77 (88,4%) pts, and incorrect in 9/77 (11,6%), proving the significance of non-invasive diagnosis in 79-98% (p=0,001) of cases. This study shows the validity of TEE in performing the diagnosis of majority of CHD in relation to invasive diagnosis. TTE represents the sovereign method of diagnosis of CHD, leaving the significant minor % (p=0,001) for diagnosis by invasive diagnostics of morphohaemodynamics of CHD, and at the same time as a chioce of adequate therapeutical tool in dealing with CHD.