The aim of this study was to examine the effects of different UV-C doses and high hydrostatic pressure (HHP) conditions on the safety and quality of minimally processed (fresh-cut) potatoes (FCP), and on the sensory properties of raw and thermally treated FCP, while observing the changes during storage. Based on the obtained results, the goal was to compare the effects of optimal UV-C and HHP treatment, as well as their combination, on the properties of FCP. In the first and second part of the research, FCP was treated with a 2% sodium ascorbate solution (SA) and vacuum packed (VP), treated with UV-C (0, 3, 5 and 10 min), and stored (23 days/6 °C). In the third part, FCP was treated with HHP (400 MPa/0, 3, 5 and 10 min) in vessels containing SA solution, VP and stored. In the fourth part, the samples were prepared as in the first part and treated: UV-C (5 min), HHP (400 MPa/3 min) and combined: UV-C (5 min)/HHP (400 MPa/3 min). 5- and 10-min UV-C treatments effectively slowed the growth of aerobic mesophilic bacteria during storage and positively affected the color and odor of raw FCP, while the thermally treated samples had a more pronounced odor and taste. The UV-C decreased the content of chlorogenic acid (CA) in raw FCP. A 5-min UV-C treatment increased the content of reducing sugars (RS) in raw and acrylamide in fried FCP, which was below the suggested limit. Thermal treatment reduced the content of CA and RS. The UV-C treated FCP maintained safety, quality and sensory properties for 15 days. Due to the similar antimicrobial effect of 5- and 10-min UV-C treatments and to save energy, 5-min UV-C was chosen for further investigations. 10-min HHP treatment significantly reduced the bacteria count. The 5- and 10-min treated samples had lower sensory scores, and showed texture damage during frying. The 3-min treatment resulted in significantly slower bacterial growth during storage and lower sensory scores for the boiled and fried FCP compared to control. For further tests, a 3-min HHP was chosen, but in VP without liquid. When comparing UV-C, HHP and UVC/HHP treatment, the greatest reduction of bacteria and their slowest growth during storage was observed in UV-C/HHP treated samples. The greatest decrease in CA was observed in HHP treated samples. All treatments increased the content of RS, significantly UV-C/HHP with a significant increase in acrylamide content of in fried FCP. The levels of PAHs were below the established limits. The acceptable sensory properties of the samples (raw, boiled and fried) remained stable during the 15-day storage period.