In cotton, the beet armyworm, Spodoptera exigua, (Hübner) are sporadic but economically important pests. Traditional control measures rely on the use of costly insecticides. Little research has been done on possible host plant resistance mechanisms. In 1998, it was observed that cotton germplasm expressing the red leaf color phenotype showed less foliar damage than normal green leaf color genotypes. In 1999, studies were performed to assess the effect of leaf color on armyworm development. Fresh leaves of closely related green and red cotton genotypes were placed in petri dishes and infested with 72 hour old larvae of laboratory reared colonies. Larval weight gain was recorded at 2 day intervals for a period of 10 days. The possible utility of cotton leaf color as a host plant resistance mechanism which functions by antibiosis was shown by the no-choice feeding studies performed.