Risk assessment has always been a serious concern in maritime transportation since shipping activities can pose potential harm to human life, commodity and maritime environment. Maritime safety researchers, in this context, are trying to enhance risk mitigation measures. This paper attempts to provide an insight into a process of accident development related to risks in ship mooring operation which presents a great challenge for ship's crew. A Fuzzy Fault Tree Analysis (FFTA) is adopted to perform systematic risk analysing on the case of ship mooring operation. The FFTA is capable of tackling limitations of conventional Fault Tree Analysis (FTA) where handling the uncertainties is possible with fuzz logic theory. A real maritime accident is analysed considering potential risks: the case of M/T Zarga which occurred during berthing manoeuvring to LNG (Liquefied Neutral Gas) terminal. The ship crew was seriously injured on his head during accident. To this end a risk model is developed and some risk control options are proposed. Besides handling data shortage in maritime risk assessment, this paper provides practical contributions to maritime professionals in course of risk mitigation and accident prevention.