The effect of boiling, roasting and autoclaving on the levels of some antinutrient factors present in the seeds of vegetable cowpea (sesquipedalis) were studied. The reduction of trypsin inhibitor was found to be highest (100%) with autoclaving at 60 min. Boiling was more effective in reducing phytic acid (68.34%) and haemagglutinin (75.98%) respectively at 60 min than the other processing treatments at the same time. The hydrogen cyanide was markedly reduced up to 81.25% at 15 min by autoclaving method while boiling at 60min resulted in (81.25%) reduction. Tannin content was reduced by boiling and roasting up to 75.00% at 60 min and 75.00% at 120 min respectively. Boiling and autoclaving at 60 min significantly reduced stachyose (60.52% - 84.21%) and raffinose (67.97 - 83.66%).