Key Inclusion Criteria:  18-40 years old (including 18 and 40 years old); Investigator's Global Assessment of subject at baseline period was at 3-4. Facial skin lesions of subject need counting as follows: 30 ~ 75 inflammatory lesions (the total number of papules, pustules and nodules is 30 ~ 75, including no more than 2 nodules), 30 ~ 100 non-inflammatory lesions (the total number of open and closed comedones is 30 ~ 100);  Key Exclusion Criteria:  Known to be allergic or hypersensitive to ASC40 tablets; Facial nodules of subject is more than 2 facial nodules The subject with cystic acne Subject with secondary acne such as occupational acne (e.g., chloroacne) and acne caused by corticosteroids (e.g., chloroacne or acne caused by drugs); Serum AST, ALT≥3ULN and Cr exceeded the upper limit of normal range