Aim This research was carried out in a descriptive and relationship-seeking design to examine the effect on the organizational climate of collegial solidarity among the nurses. Background It is important that nurses work in an organizational climate where they can be in solidarity with their colleagues to offer quality service and to deal with all the problems they face. However, the impact of collegial solidarity on the organizational climate is not yet clear enough. Methods This study was performed with a cohort of 333 nurses working in a university hospital in Turkey. Data were collected using the personal information form, the Colleague Solidarity of Nurses' Scale and the Organizational Climate Scale. The data were evaluated using Cronbach's alpha coefficient, frequency and percentage distribution, the Pearson product-moment correlation coefficient and a simple linear regression analysis. Results A relationship was identified between the collegial solidarity among nurses and the organizational climate. We have determined that collegial solidarity effects organizational commitment, teamwork, supportive climate, stress, negative interaction, human relations, job satisfaction, hierarchy, and the communication and innovative climate. Conclusion Collegial solidarity among nurses has effects on the organizational climate. Implication for nursing policy and health policy It is recommended that executive nurses support the colleague solidarity between nurses in healthcare settings, in particular by reducing stress in nurses, strengthening teamwork and communication and, thus, making the organizational climate more positive.