In today's dynamic competitive business environment, employees are crucial for organisational sustenance and growth. Organisational leaders should be more focused on employees' abilities to enhance innovative behaviour and apprise different roles in organisations. This study compares leadership styles (Ethical and Relational) and identifies the effects on the innovative work behaviour of managers in the Yemeni transportation sector. A random sample of 364 managers working in the three main cities (Aden, Hadramout, Hodeida) in Yemen was selected. Four measurement scales are integrated to develop the research instruments. The ethical leadership survey (ELS) measures the managers' ethical leadership styles, the relational leadership questionnaire (RLQ) detennined the relational leadership style, and the employee innovative work behavior scale and organisation culture index (OCI) were also integrated. Statistical Package for the Social Sciences SPSS.20 and AMOS software for Structural Equation Model (SEM) were used for conducting the quantitative data analysis. The major findings of the study were that the relational leadership style has a significant positive effect on employee innovative work behaviour while ethical leadership did not have a significant positive effect. Furthermore, organisational culture plays a mediating role between the relationship of leadership styles and employee innovative work behaviour.