Sophisticated customer demands and advanced technology have changed the way of conducting business. Financial condition of a manufacturing company largely depends on the defect rate of a product. Understanding the key features, obstacles, and shortcomings of the six sigma method allows organizations to better support their strategic directions, and increasing needs for coaching, mentoring, and training. The objectives of this paper are to study and evaluate processes of the case organization, to find out the current sigma level and finally to improve the existing Sigma level through decreasing defects. According to objectives, current sigma level has been calculated, manufacturing process analyzed and suggestions given for improvement. Especially in analyzing phase different analysis tools like Production Layout, Process Block Diagram, Cause and Effect Diagram, Cheek Sheet, Process control chart are used. FMEA is used as improvement tool. By using this it has been possible to improve productivity by reducing defects rate. This research work has been carried out in a cement manufacturing company to show how to implement Six- Sigma in this type of industry. This research related work does not only apply to cement manufacturing company but also in any other types of organizations. By implementing Six-Sigma a perfect synchronization among cost, quality, production time and control time can be achieved.