Background/Objectives: Patient safety culture represents a holistic approach to ensuring the safety of patient care. When nurses experience abusive behaviors, patient safety culture is undermined. Methods: A cross-sectional study was conducted in Greece, and data were collected via an online survey between October and December 2025. Workplace gaslighting and patient safety culture were measured using the Gaslighting at Work Scale and the Safety Organizing Scale, respectively. Multivariable linear regression analyses were performed using IBM SPSS Statistics 28.0. The level of statistical significance was set at 0.05. Results: The sample included 448 nurses. Almost nine out of ten of the participants (87.3%) were women, with an average age of 38.04 years (SD = 10.27). Regarding educational level, 42.2% held a MSc or PhD degree. Respondents reported moderate perceived workplace gaslighting with a mean score of 2.37 (SD = 1.04) on the Gaslighting at Work Scale. For safety culture, the Safety Organizing Scale yielded a mean score of 5.00 (SD = 0.91). In the univariable analysis, workplace gaslighting was significantly and negatively associated with safety culture (beta = -0.195, 95% CI = -0.275 to -0.115, p < .001), indicating that higher levels of workplace gaslighting were related to worse safety culture behaviors. This association was still significant even when potential confounding variables were considered (adjusted beta = -0.223, 95% CI = -0.305 to -0.142, p < 0.001). Conclusions: This study highlighted the negative impact of workplace gaslighting on patient safety culture. Healthcare organizational leadership is urged to establish and enforce zero-tolerance policies toward gaslighting behaviors and to foster an environment in which nurses are encouraged to speak up openly and report such behaviors.