Micro-injection moulding is a complex processing technology with many parameters to control. Micro-injection part defects are difficult to evaluate because of its qualitative nature. This makes difficult to choose the correct parameter combination derived from the analysis of the part defects. An intelligent decision making system has been developed. This system is based on fuzzy logic techniques, and it is oriented to advice in the machine setting. The system guides to the operator to establish the priority of intervention, and the magnitude of change needed over the Micro-injection parameters. Micro-injection tests have shown the effectiveness of the developed system. Considerable time reduction has been achieved in the machine setting.