This mater thesis is concerns to test that if financial patterns of listed firms in energy sector of Pakistan follow any foremost capital structure theories. The analysis was implemented on a sample of 22 listed firms during the period 2001 to 2005. The results of pooled regression model show that both Static trade-off theory and Pecking order theory are pertinent corporate capital structure theories to the firms in Pakistani energy sector.

Theoretical perspective: The theoretical framework includes the corporate capital structure theories and modern research work in this field. Hypotheses are formulated on the basis of theoretical background. Methodology: Regression model is used to analyze the data taken from Pakistani firms in energy sector, listed on Karachi Stock Exchange, during the period 2001-2005.