Staining of blood films remains one of the most essential part of haematology. The different blood cells have different intracellular structure that take up stains according to chemical nature. Leishman stain is one of the Romanowsky stains used in the haematology laboratory for the staining of blood films. It contains methylene blue and eosin dye prepared in an alcohol medium and is diluted with a buffer. Phosphate buffer is used during Leishman stain as it acts as a mordant enhancing staining reactions and it is the recommended and best buffer for staining. Aim This comparative study was aimed at determining if different water samples used as buffer show significant effects on the morphology of blood cells during Leishman staining. Methods pH analyses of different water sources such as water from borehole, waterboard, rainwater, fridge water, distilled water and air conditioned water were carried out and used as buffers to carry out Leishmann staining on blood films. The stained slides were examined macroscopically and microscopically using 100x objective. Results The study has shown that deionized and tap water used as buffer could produce moderately good film with well stained red cells, white cells and platelets. Rainwater, distilled, fridge and air conditioned water showed a significant change in the morphology of blood cells both in an apparently healthy film and a diseased film Conclusion This study demonstrates that deionized water and tap water devoid of chlorine can be used as substitutes in the right pH of 6.8 in a situation where phosphate buffer is not available. It is therefore recommended that quality control should be carried out to check the quality of stains and buffer used for staining films in order to produce quality results.