Medical devices are significant risk when, among other things, they could be implant, invasive,life-supporting, or substantially important for diagnosing, curing, mitigating, treating, or preventing impairment of humans. Especially, medical software is a specialized branch of software engineering in which the software is used to monitor or control patient functions and records. Once a malfunction or a latent design flaw in the software of medical device could lead to an erroneous diagnosis or a delay in delivery of appropriate medical care that would likely lead to injury, even serious harm or death. According to ISO14971 for risk management of medical device, this paper attempts to analyze the example of the Picture Archiving and Communication System (PACS). All of the risks would be implemented the analysis and done the necessary control by the ISO14971 relevant procedures; and any undesirable hazards would have
been reduced to the acceptable levels.