This study investigates the impact of capital structure on the performance of quoted conglomerates firms in Nigeria by analyzing the relationship between financial performance measured by return on asset (ROA), earnings per share (EPS) and net margin (NM) with Short

 term debt and long term debt. Two variables also identified in literature to have influence on firm performance, namely size and efficiency are used as control variables. The study covers seven (7) conglomerates firms in Nigeria for the year 2002 through 2011. Panel data for the

 selected firms were generated and analysed using Generalised least square (GLS) with the application Random effect regression model as a method of estimation. The study reveals that short term debt has significant negative impact on all the three accounting measure of performance studied. The result also reveals that long term debt has significant negative impact on both return on asset (ROA) but not significant with respect to earnings per share (EPS) and net margin (NM). The study concludes that capital structure has significant negative impact on financial performance of quoted conglomerates firms in Nigeria for the period under study.

 Therefore, it is recommended that quoted conglomerates firms in Nigeria should reduce debt levels in their capital structure so as to enhance their financial performance.