The effects of changing in composition and adding of coconut oil and milk powder on physical states and rheological properties of cocoa powder/cocoa butter mixtures were investigated. The aim of this study is to keep the product quality at the right temperature and then consumer's acceptance. The viscosity, hardness and the solidification temperature of cocoa powder/cocoa butter mixtures reduced when cocoa butter content increased or cocoa butter was replaced by coconut oil, or cocoa powder was replaced by milk powder. The viscosity (at 31oC and 50oC) significantly decreased in accordance with an increase in cocoa butter (from 40 to 50%), addition of coconut oils (from 10 to 20%) and replacement of cocoa powder by milk powder (from 5 to 10%) by weight. The cutting and breaking hardness of mixtures (at 10oC and 20oC) decreased sharply when the cocoa butter content was more than 50% of the mixture by weight. The solidification temperature of mixtures decreased from 24oC to 20oC when the coconut oil ratio increased from 20% to 40% of mixture weight