The purpose of this study is to evaluate the quality of a bilayer tablet containing a sustained-release metformin layer and an immediate-release linagliptin layer, developed for the treatment of type 2 diabetes, and to establish quality control standards for its consistent quality management. To evaluate the release rate control mechanism, chemical stability, and sensitivity to temperature and humidity, which are key pharmaceutical factors of this bilayer tablet, comparative dissolution testing and stability testing of NDMA impurity and dissolution testing were conducted. As a result of the comparative dissolution testing, the sustained-release metformin layer showed an f2 value of 71.33 in dissolution medium of pH 6.8, and the immediate-release linagliptin layer showed average dissolution rates of 89.8 %, 94.9 %, and 99.6 % for the comparator product and 91.8 %, 95.3 %, and 101.2 % for the test product within 15 minutes in dissolution media of pH 1.2, pH 4.0, and pH 6.8, respectively. The NDMA impurity was not detected, and met the acceptance criteria of below 0.048 ppm, and the dissolution test met the dissolution test criteria, confirming stability under long-term stability conditions for 12 months and accelerated stability conditions for 6 months. Therefore, the quality control standards for the bilayer tablet containing linagliptin and metformin with immediate- and sustained-release properties are established.