(1) Background: Several researchers have highlighted a higher incidence of overweight and obesity among nurses, and others have analyzed the quality of nurses’ eating habits and their related physical activity levels. The present study assessed the differences in personal habits among Italian oncology nurses according to sex, work experience and shift. (2) Methods: A cross-sectional study was performed during September–October 2023. A Google Moduli questionnaire was created and divulgated through Facebook and Instagram “Nurseallface” social pages. (3) Results: A total of 306 Italian oncology nurses agreed to participate in this study. Significant differences were reported between sex and the nutrition dimension (p = 0.018); male nurses reported higher levels in this dimension (2.69 ± 0.43) than females (2.56 ± 0.49). By considering the role of work experience in the health-promoting lifestyle profile, significant differences were recorded in the physical activity sub-dimension (p < 0.001), especially among nurses employed for more than 30 years who reported higher levels of physical activity (5.25 ± 0.23) than the other groups. By considering the shift role in the health-promoting lifestyle profile, significant differences were recorded with a health-promoting lifestyle general score (p = 0.046), especially among nurses employed only during the morning shift who recorded higher levels in health-promoting lifestyle than the others (one shift: 2.49 ± 0.29 vs. two shifts: 2.47 ± 0.24 vs. three shifts: 2.41 ± 0.25). Additionally, significant differences were reported in the physical activity dimension (p = 0.017), since nurses employed only during the morning shift recorded higher levels of physical activity than the others (one shift: 2.96 ± 1.28 vs. two shifts: 2.55 ± 0.94 vs. three shifts: 2.48 ± 1.20). Finally, a significant difference was recorded in the nutrition dimension (p = 0.017), since nurses employed during the morning and the afternoon shifts recorded higher levels of nutrition than the others (two shifts: 2.73 ± 0.39 vs. one shift: 2.63 ± 0.43 vs. three shifts: 2.56 ± 0.51). (4) Conclusions: Nurses represent the motive of healthcare organizations. Promoting healthy lifestyles among nurses would help healthcare organizations to have a healthy workforce, and nurses themselves can be advocates for policies to improve patient lifestyles and improve chronic disease prevention.