The introduction to the Fault Tree Analysis has been presented in this article. Selected publications on the Fault Tree Analysis have been listed. The usefulness of the method in marine engineering application has been indicated. Reliability testing facility has been presented, that is typical two-stroke, slow-speed ship crosshead Diesel engine intended to power the ship. The way of creating system model with the Fault Tree Analysis application has been presented. Reliability structure of tested engine has been modelled using Reliability Block Diagrams, as well as the Fault Tree Analysis. Main tree describing the object reliability structure analysis and the sub-tree structure modelling crank system, subsystem of the cam shaft, cylinder exemplary system and turbocharger have been built. Qualitative analysis of the tree has been conducted – the minimal cut sets of the system has been determined. The directions for further research have been indicated.