Many manufacturers, including Lenovo, Sony, Procter & Gamble, and Buckle, have adopted differentiated distribution channels to market vertically differentiated products. However, there is scant literature addressing the issue of quality differentiation in the presence of differentiated distribution channel policies. To fill this void, we examine whether (how) differentiated channel policies affect manufacturers' quality differentiation and all parties' performance. Specifically, we consider a manufacturer who produces two vertically differentiated products (high-and low-tier ) together, but with two marketing options: (1) distributing both products through one retailer (Model O, One-channel policy), or (2) providing high-quality products through one channel but low-tier products through another (Model T, Two-channel policy). Our results show that the manufacturer is more likely to decrease the level of quality differentiation in Model T than in Model O. Moreover, contrary to popular belief, we show that "quality distortion" is not limited to low-tier products but can occur with high-tier products.Among other results, we find that the one-channel policy benefits the retailer but hurts both the manufacturer and the total supply chain. To test the robustness of the results, we also comment on how the additional horizontal consumer heterogeneity affects our results and the implications of the competition at the manufacturer level.