Background: The apical epithelial surfaces of mammalian respiratory, gastrointestinal, and reproductive tracts are coated by mucus, a mixture of water, ions, glycoproteins, proteins, and lipids. Mucins are mainly of two typesNeutral and Acidic. Objectives: To know the mucin distribution of the breast in malignant lesions. Methodology: This is a retrospective, observational , analytical, case control study aimed to evaluate mucinshisto-chemical pattern in malignant breast. Twenty five histologically proven malignant human breast tissue were taken. Tissue sections were stained by Mayer’s Haematoxylin and Eosin, PAS, PAS-diastase, Phenylhydrazine-PAS, Alcian blue 2.5, Alcian Blue 1, combined alcian blue-PAS, Aldehyde Fuschin and combined aldehyde fuchsin-alcian blue techniques. Results: Results were tabulated according to color intensity into different grades ranging from + to ++++. Regarding mucin histochemistry of malignant breast - ”sialomucins” were seen predominant than neutral and sulphomucins. Conclusion: Mucin histochemical patterns have valuable, cost-effective, and important role where a slight change in the mucin pattern may help in the early diagnosis of the disease process. Mucin histochemistry may provide a valuable and cost-effective tool for the diagnostic histopathology and for the researchers in histology.