According to the World Health Organization it is estimated that 80% of the world population, somehow, uses plants to treat diseases. Despite the wide variety of synthetic drugs (many originating related to the natural environment), interest in the knowledge of the morphology, chemical composition and pharmacological properties has increased especially when it comes to Brazilian plants. Costus spicatus plant has attracted the attention of researchers because it was found in the rhizomes just a new source of diosgenin, a precursor of steroid hormones. Also, for phytochemical studies of the aerial parts of the plant, have been described recently, two new diglycosides flavonids: a tamarixetin 3- neohesperidoside and canferol 3-O-neohesperidoside. Other quite well known compounds 3-O- neohesperidoside flavonoids quercetin and six were identified. These flavonoids diglycosides had proven anti-inflammatory activity. However, there are no studies proving the efficacy and safety of the use of this plant for therapeutic purposes. The objective of this study is to evaluate the spectrophotometric standard of a Costus spicatus extract and its effect on red cell membrane level. Wistar rat blood samples were collected and incubated with different saline concentrations and samples the buffered and unbuffered extract. The spectrophotometric reading of the extract was performed at different concentrations and the percentage hemolysis was determined. Based on the analysis of the results was possible to speculate that the extract has in its composition phenolic molecules with anti-hemolytic and saponins molecules which could be responsible for hemolytic action.