As film products are more frequently used from producing traditional flexible packing products to high-tech electronic products, requested higher level of quality. Most film products are made in the shape of roll-type finished goods, so various quality problems are addressed related with their characteristics of shape. Thickness of film products is one of the most common and important quality problems. Particularly the Degree of thick smoothness is more important than other thickness issues, because it causes many secondary issues of thickness-related quality problems like wrinkles or faulty windings. Thick smoothness must be controlled in both horizontal and vertical direction. In this paper, HOQ (house of quality) was built to interpret VOC (voice of customers) to CTQs (critical to quality). To decide priorities of VOC and CTQs, both techniques are applied. One is AHP (analytic hierarchy process) with pairwise comparison. The other is an absolute weight calculation method with level-up rate. From the result of HOQ, it is certain that the thick smoothness is the most important CTQ in film manufacturing industry. Finally, this paper presents how to monitor and improve repetitive coincidence of microscopic deviation of thickness in some special vertical points.