The purpose of the study is to testify the efficacy of treating moderate-to-severe acne vulgaris with Single Microneedle Radiofrequency, and provide evidence for the hypothesis that "whether Single Microneedle Radiofrequency therapy could be an alternative to photodynamic therapy for moderate to severe acne vulgaris."

The purpose of the study is to testify whether Single Microneedle Radiofrequency is effective for moderate-to-severe acne vulgaris, through treating moderate-to-severe acne vulgaris patient for 1 month, using photodynamic therapy as controlled group, and try to provide clinical evidence for the hypothesis that "whether Single Microneedle Radiofrequency therapy could be an alternative to photodynamic therapy for moderate to severe acne vulgaris."

Inclusion Criteria:

1. Consistent with the diagnostic criteria of moderate-to-severe acne vulgaris (IGA3-4) .
2. Age of a subject is older than 14 and is younger than 45.（including 14 and 45）.
3. Did not take any anti-acne treatment in the last 1 month, and did not take part in any clinical trial.
4. Informed consent is signed by a subject or his lineal relation.

Exclusion Criteria:

1. systemic acne treatment with oral isotretinoin within 6 months or oral antibiotics in the past 1 month;
2. history of facial procedures like dermabrasion, chemical, or laser peels;
3. history of photosensitive diseases, porphyria, or porphyrin sensitivity.
4. With serious protopathy or disease of cardiovascular, liver, renal, gastrointestinal, hematological systems and so on.
5. Pregnant women or women in lactation.