Foetal arrhythmia is defined as any irregular foetal cardiac rhythm or regular rhythm at a rate outside the reference range of 120 to 160 beats/minute. Foetal echocardiography permits accurate determination of the structural characteristics and the nature of the arrhythmia in foetuses. It is particularly indicated for mothers from high-risk groups. Management of diagnosed heart disease, including foetal arrhythmia, leads either to the termination of pregnancy or to optimal postnatal care of baby and mother. This retrospective study examined the application of foetal echocardiography in the diagnosis of foetal arrhythmia and its clinical significance.