Although nursing is the main area of interest in the curriculum of the specialist ambulance nursing program in the advanced level of education, there has been reported a lack of knowledge about nursing in within the ambulance service. The aim was to explore specialist ambulance nurses’ perceptions of nursing, which were explored by employing a phenomenographic approach. The study comprises individual interviews with 19 strategically selected specialist ambulance nurses. The results showed seven descriptive categories emerged detailing the variations in how the specialist ambulance nurses perceive, understand, and conceptualize the phenomenon of nursing in the Swedish Ambulance Service. Four categories revealed the specialist ambulance nurses’ qualitatively different perceptions of nursing, i.e., their role and responsibility, while three showed perceived barriers to assuming their role and responsibility, comprising culture and leadership, conditions, and framework. The seven categories are outlined in the outcome space. In conclusion, there is a very wide variety of perceptions of ambulance nursing within the Swedish Ambulance Service. There is a need for implement the nursing process both in the Specialist Nursing Pre-hospital Emergency Care education curriculum and within clinical practice. Further, there is a necessity to develop and implement nursing guidelines in the ambulance.