To demonstrate the efficacy of SHR-1314 at Week 12 in subjects with proliferation lupus nephritis in terms of improvement of 24h UPCR, compared to placebo. The study will also assess the safety and tolerability of SHR-1314 in the patient population over the study period.

Inclusion Criteria:

1. Chinese adult pts (18-65yr), Male or Female

2. BMI≥18 kg/m2 and ≤ 35kg/m2

3. Confirmed diagnosis of LN, renal biopsy report data is within 3-months prior to the date of ICF is first signed

   3.1 Biopsy-proven proliferative lupus nephritis Class III or Class IV, either with or without the presence of Class V, using the 2003 ISN/RPS criteria.

   3.2 24h UPCR ≥ 1 at screening.

   3.3 24h UPR ≥ 1.0 g/d，≤ 3.5 g/d.

   3.4 eGFR > 45ml/min/1.73m2.

4. SLEDAI-2K≥8.

Exclusion Criteria:

1. Significant medical Problems like myocarditis, pericarditis, severe manifestations of neuropsychiatric SLE (NPSLE)
2. Subjects who have previously treated by both CYC and MMF (or other forms of mycophenolate)
3. With a hHistory of using 60 mg/d prednisolone (or equivalent dose) for more than 3 months prior to Baseline
4. History of inflammatory bowel disease or have other ongoing active autoimmune diseases
5. Required management of acute or chronic infections within the past 8 weeks.
6. At screening, history or symptoms of malignancy of any organ system, treated or untreated, within the past 5 years, regardless of whether there is evidence of local recurrence or metastases.
7. History of congestive heart failure (New York Heart Association [NYHA] functional classification ≥III), cerebro-cardiovascular events, or serious bleeding events at screening and / or randomization that in the judgement of the Investigator prevents the subject from participating in the study.
8. History of depression and/or suicidal ideation or any suicidal behavior based on an assessment using the Columbina Suicide Severity Rating Scale (C-SSRS) at screening and baseline . The subjects will be exluded if any answer to question is "yes" in the questionnaire orare clinically judged by the investigator to be at risk for suicide
9. Receipt of any IL-17/IL-17R targeted therapy within the past year.
10. Those who have participated in any clinical study for any drug or medical device within 3 months before screening.
11. Tested positive for human immunodeficiency virus (HIV), hepatitis B, or hepatitis C.
12. All subjects will be tested for tuberculosis status using IGRA and X-ray test. Subjects with active or latent tuberculosis will be excluded
13. History of severe allergic reaction to contrast agents or biological medicines.Current drug or alcohol abuse or dependence.
14. History of severe allergic reaction to contrast agents or biological medicines.Current drug or alcohol abuse or dependence.
15. Pregnant or nursing..