Flavoring seasonings are food additives added with the aim of increasing flavor(palatability) and covering up deficiencies in food in terms of taste. The natural glutamatecontent of mushrooms has the potential to be used as a flavoring ingredient, one of which isoyster mushrooms. The quality of natural flavoring of oyster mushrooms is determined by theformula of the ingredients and the way they are produced. The drying process can affect thewater content and color of seasoning. This study aims to determine the water content and natural flavoring of oystermushrooms based on initial treatment. This study was an experimental study using aCompletely Randomized Design with 6 treatment trials (non-blanching, blanching, sodiumbisulfite immersion, citric acid immersion, blanching + sodium bisulfite immersion, andblanching + citric acid immersion), and 3 test replications. The moisture content test wasperformed by the AOAC oven method and color analysis was measured using Konica MinoltaCR-10 Color Reader. Observational data were analyzed using univariate analysis. The results showed that the initial treatment had a tendency to increase water content.Moisture content for all samples based on pretreatment meets the quality criteria for dryproducts that is 10%. The results of the color analysis showed an increase in the value of eachtreatment but did not show any real difference in color. The treatment using sodium bisulfiteimmersion and blanching showed an increase in brightness intensity and a good chroma valuecategory compared to the control value. Based on Hue value in each treatment has the samecolor scheme, namely yellow – red. OKeywords: Oyster mushroom, Water Content, Color, Pre treatment, blanching