The stability of red pepper seed oils during storage at 20${pm}$3$^{circ}C$, 40${pm}$3$^{circ}C$ and heating at 140${pm}$3$^{circ}C$ or 180${pm}$3$^{circ}C$ were measured to evaluate red pepper seed oil as a cooking oil. Two species of red pepper seeds (native, improved) were dried by either sunlight or heating to prepare the oil samples of NS (native, sunlight-dried), IS (improved, sunlight-dried), NF (native, heated), and IF (improved, heated). During storage at 20${pm}$3$^{circ}C$ or 40${pm}$ 3$^{circ}C$, acid values (AV) of all red pepper seed oils were higher than that of soy bean oil (SBO), however, peroxide values (POV) were similar to SBO. Antioxidative stability of NS was better than SBO but IF was not. By the heat treatments at 140${pm}$3$^{circ}C$ or 180${pm}$3$^{circ}C$, NS was identified to have better antioxidative stability than SBO and IF was the lowest. In sensory evaluation of each deep-fat fried potato-chip at 180${pm}$5$^{circ}C$, potato-chips fried in NS were better than that of SBO for color, taste, and flavor. NS-fried potato-chips got the highest score in overall acceptance (p<0.05), however, those of IF showed little acceptance. When blended oils (SBO: NOS, 0, 25, 50, 75%) were used, 50% blended oil was the best for taste, color, flavor, cripness, and total acceptance.