Skin cancer is nowadays one of the most common types of cancer in most countries of the world and its number is constantly increasing. The reason for this primarily lies in increased exposure to the sun (UV rays), longer lifetime (skin cancer is more common in old age) and thinner ozone layer. The objective of this paper is to introduce the most common precancerous lesions and skin tumours, which in recent years appear more frequently and with increasingly younger population, primarily in order to enable the pharmacist, as one of the most accessible health care professionals, to recognize the listed conditions and promptly refer the patient to the doctor. The paper deals with actinic keratosis as one of the most common precancerous lesions, and squamous cell carcinoma, basal cell carcinoma and melanoma, the most common malignant skin tumours that occur as a result of UV exposure. Furthermore, the paper discusses the preventive measures to be followed in order to avoid the stated conditions, where again the pharmacist has the key role in educating the population as well as in selecting adequate protection for each individual patient. According to available literature, this paper analyses types of sunscreens present on the market, their characteristics, advantages and disadvantages and the applicable regulations relating to such preparations. In addition, there was discussion about antioxidants that are thought to be able to absorb some of the resulting free radicals that occur in the skin as a result of excessive exposure to UV radiation. Antioxidants may be particularly useful for skin changes caused by UVA radiation, which are largely determined by oxidative process. Long-term clinical trials are needed to determine the effectiveness of these products, however they are not dangerous and can be effective, which is why they are mentioned in the paper. The notion of secondary prevention refers to early detection and diagnosis of malignant skin tumours which enables higher cure rate and reduces mortality. It is necessary to regularly conduct self-examination of face and body in order to timely detect skin changes. It is also necessary to periodically have the skin examined by a dermatologist, and persons with an increased risk of skin tumour should undergo a dermoscopic examination every 6 months or more often. Both for primary and secondary prevention of malignant skin tumours it is important to educate the public and to implement appropriate measures for the early diagnosis and early treatment by all health care professionals, including pharmacists.