Water is a component of every pharmaceutical product, so water system must be validated to ensure the consistent production of high quality water. The pharmaceutical industry places a high priority on the quality of water used in production of finished product, intermediate reagent preparation and analytical processes and especially in case of parenteral products where quality of water must be as per Pharmacopoeia.According to WHO TRS 937 and EU Guideline, critical quality impacting systems such as water system should be qualified and validated. Here qualification should be performed before validation is performance. Hence, control of the quality of pharmaceutical water throughout the production, storage and distribution processes is a major concern. A risk assessment approach may be applied to pharmaceutical water system a part of utility according to guideline ICH Quality Risk Management (QRM) Q9, Annex II.4. Validation of water purification system was performed in three phasesby applying various chemical and microbiological tests as per IP and BP. To adopt FMEA tool for Risk assessment of critical factors affecting quality attributes of pharmaceutical Purified water system.