Systemic lupus erythematosus (SLE) is one of the common autoimmune disorders that affect women during their childbearing years. Disease activity frequently increases during pregnancy and the postpartum period, representing a challenge for both the patient and the treating physician(s). We report a case of successful management of lupus nephritis flare in the first trimester. The patient developed bilateral leg edema and nephrotic-range proteinuria of 5 g/day. She was treated with steroids and tacrolimus, which resulted in the induction of remission during pregnancy. The patient reached full-term with no maternal or fetal complications. This case indicates that tacrolimus, which is convenient to use and has limited adverse effects, may represent a potential safe and effective treatment option for SLE nephritis during pregnancy.