Malignant melanoma (MM) shows rapid increase in the incidence and it is the most common cause of death due to skin cancer. On the other hand, MM can completely be removed in patients noticing the lesions early and applying to physicians on time. Thus the life expectancy of these patients is not altered. Although MM can occur in every individual, it is more common in patients with some of the established risk factors such as fair skin, increased sun exposure, genetic basis (CDKN2A mutation), and existence of increased number of melanocytic nevi and/or dysplastic nevi. A specialized care of patients with risk factors and their regular follow-up is critical to lower the mortality and morbidity in MM. Early diagnosis of MM prevents metastasis and decreases mortality rate. Nowadays, there are many newly developed imaging methods to help the clinicians before biopsy. However, the suspicion of MM should initially be based upon major clinical findings of the lesion subject to changes during the evolution of the tumor. In this review, risk factors of MM will be summarized and clues for early diagnosis of this dangerous tumor will be discussed.