Milk and butter are among the precious foods susceptible to spoilage and rancidity due to psychrotrophic microorganisms' activities, which grow in abundance due to the richness of milk and butter in the nutrients and their ability to resist the cold environment milk and butter are stored. In this study, the total psychrotrophic bacterial and fungal counts were recorded. The rancidity represented by the Thiobarbituric acid reactive substances value and aflatoxins B1 and M1 levels were also measured by high-performance liquid chromatography. The results reflected a strong correlation between the total number of psychrotrophic bacteria, the rate of rancidity and the total number of molds, and the levels of the aflatoxins in the milk and butter. In conclusion, the psychrotrophic bacterial and mold counts in the milk and butter must be monitored carefully and be added as a routine examination to the list of the butter examinations.