Morphology and seed germination of Reseda lutea L. (Resedaceae), which is distributed naturally in Turkey, were investigated. Germination trial was observed at 10, 15, 20, 25, 30, 35 and 40°C. In laboratory conditions at 25°C, 87% of the seeds of R. lutea germinated, while in soil conditions, the best germination rate was only 23%, achieved with seeds sowed at 10 mm depth. The results of germination under different light conditions showed that the germination rate at 25°C in continuous darkness was 87%, 76% with 6 hours of light, 67% with 12 hours of light, 52% with 18 hours of light and 42% with continuous light. Measurements of samples collected from different localities showed that the length of the plant is inversely proportional to the altitude.