Introduction: This is a case of new-onset systemic lupus erythematosus (SLE) manifesting as acute pneumonitis during pregnancy . No prior reports have documented pneumonitis as the presenting manifestation of SLE in pregnant women . Case Presentation . A 23-year-old pregnant female presented with high-grade fever, cough, arthralgias, and respiratory failure . Infectious workup was negative . She was positive for ANA, anti-dsDNA, anti-SSA, hypocomplementemia, and pulmonary infiltrates, supporting the diagnosis of SLE and pneumonitis . The patient received methylprednisolone achieving adequate clinical and serological response . Conclusion: When SLE patients present with fever, cough, and respiratory failure, pulmonary infiltrates should raise the suspicion of pneumonitis in the absence of infection and hemorrhage . Even though acute lupus pneumonitis (ALP) is rare and seen only in 2% of SLE patients, a high index of suspicion aids in prompt diagnosis of this life-threatening condition . Also, positive anti-SSA antibodies may be associated with lupus pneumonitis.