The sample data was comprised of non-financial firms listed on Karachi Stock Exchange, Pakistan from 1993 to 2002 excluding banks, insurance companies, and investment companies. We were taken the debt to total assets ratio as a proxy for leverage (dependent variable) that was measured following ways mentioned in previous studies (Jensen (1986), Harris and Revive (1990) and Banerjee, et al., 2000). For potential determinants of leverage, we study four independent variables namely tangibility, size, growth and profitability. Variables affecting leverage ratio were calculated by dividing the total debt by total assets and 3-variables were significantly related to leverage ratio whereas the remaining variables were not statistically significant in having relationship with the debt ratio. Our results showed that tangibility variable confirms tradeoff theory, Growth (GT) variable confirms the agency theory hypothesis and Profitability (PF) confirms the predictions of pecking order theory.