The aim of this study was to determine the effects of wilting and additives on fermentation quality and nutritional value of round baled rice straw silages. A 2 × 4 2 factors experimental design was used. Four treatments were allocated both on fresh and 24-h wilted rice straw harvested on the end of October. The dry matter content were 36.5% and 42.3% for fresh and wilted straw, respectively. The 4 treatments were control, 2.5% molasses (FM basis), silage inoculant, and both of 2.5% molasses and silage inoculant. The inoculant was applied at twice the recommended rate of 10 mg/kg fresh forage to supply 2 × 10⁵ cfu/g of a mixture of homofermentative Lactobacillus plantarum and Pediococcus acidilactici. Each treatment was applied in triplicate. After rice straw was round baled and ensiled for 50 d on open cement floor at 10°C to 18°C, each silage round bale was open for sensory quality evaluating and sampling for fermentation parameters and nutrient composition analysis. Results showed that regardless of condition of rice straw it was hard to achieve good silage, one silage bale in 3 with visible white mold and light musty odor. Molasses or inoculant alone could not improve fermentation quality and nutritional value of rice straw silages, except that inoculant decreased NH₃-N/TN and molasses decreased structural carbonhydrate content. Combining additives increased acetic acid, propionic acid, and CP content, but structural carbohydrate content decreased. The same treatment increased butyric acid concentration in the wilted rice straw. Wilting decreased dry matter recovery of rice straw silage, with increases in CP content and ammonia-N concentration. In all, additives such as molasses or inoculant alone could contribute rice straw ensiling success. It needs further study to evaluate and determine whether rice straw should wilt or add both molasses and inoculant before ensiling with low moisture content.