Abstract Cognitive Diagnostic Assessing (CDA) aims to determine whether or not examinees have mastered attributes or skills underlying according to their responses to test items, it provides a more detailed evaluation of the strengths and weaknesses of students. It aims to remedial teaching, which can make students understand own knowledge state in-depth, realize self-learning. It also can achieve “teaching students in accordance with their aptitude” which is a thousands of years dream when teachers conduct targeted teaching according to the specific ability of the students. CD-CAT is one of the most successful application. It has the characteristic of cognitive diagnosis and adaption at the same time. It can evaluate the knowledge state of candidates in a short time with fewer questions. Due to classification of the ideal master patterns, the existing CD-CAT could not handle too many attributes. The number of ideal master patterns increases exponentially with the raise of the attribute number. For example, when the attribute number is 4, the category of ideal master pattern is 24=16, when the attribute number increases to 8, the category of ideal master pattern is 28=256. The attribute number is controlled in 4-8 within a unit in teaching practice. When the unit number increases, the attribute number is always more than 10, the existing CD-CAT could not handle under the granularity attribute level. The module of CD-CAT could be considered as a block, CD-MST is a few blocks. CD-CAT is adaptive at item level, it can be seen as one block. This study combined CD-MST and CD-CAT, presented a new adaptive testing—Cognitive Diagnostic Blocked Adaptive Testing (CD-BAT), which adopted dynamic and unique ideal master patterns to each examinee to control the issue of traditional CD-CAT attribute number limited. The simulation study showed that when the attribute number was 8, CD-BAT had slightly advantages than traditional CD-CAT. The reason was that the CD-BAT revised the attribute after the first block. When the attribute number was 12, the PCCR of CD-BAT was deceased, the ACCR appeared an upward trend. In other words, due to the increasing of the attribute number, the accurate of the whole pattern was decreasing, the accurate of the attribute was increasing.