[Objectives]  To explore the effect of supplementary nutrients, and the background color of oviposition sites, on the reproduction of adult Mythimna separata (Walker) in order to provide a guide for rearing this species in the laboratory.  [Methods]  Eight kinds of supplementary nutrients were chosen; 5% honey solution, 10% honey solution, 10% glucose solution, 0.2 mol×L^﹣1 maltose solution, 5% glucose+5% honey mixture, 5% fructose+5% honey mixture, 5% glucose+5% fructose mixture, and a mixture of sugar-acetic acid-ethanol (3 parts white sugar, 1 part white vinegar, 4 parts white wine and 2 parts water). Six colored, plastic ropes; red, yellow, green, blue, purple and white, were selected to test the color preferences of females during oviposition. The study included the pre-oviposition and oviposition periods, and measured adult longevity and fecundity under the different treatments. [Results]  Adults fed on the 5% glucose + 5% fructose mixed solution and the 0.2 mol×L^﹣1 maltose solution, had the highest fecundity, whereas that of those fed on sweet and sour wine was significantly lower than all other treatments. No significant differences was found among the other five supplementary nutrient treatments. Of the six different colors tested, adults preferred blue, and the fecundity of adults was significant higher on blue than on other colors. Fecundity was lowest on red and white and intermediate on yellow, green and purple. [Conclusion]  A solution of 5% glucose +5% fructose, or 0.2 mol×L^﹣1 maltose, and a blue background, are the optimal nutrient and color conditions for the reproduction and growth of M. separata under laboratory conditions.