We report a case of acquired factor XI deficiency with lupus anticoagulant (LA) in a 28-year-old primigravida who presented with finger pain and eruptions on her palms and fingers during the 3rd trimester of pregnancy. The patient complained of pain and reddening of the fingers at 30 weeks of gestation. She was referred to our tertiary center with a diagnosis of preeclampsia and suspected collagen disease at 35 weeks of gestation. Erythema was seen on the fingers and palms, and she presented with pain and cryesthesia on the fingers. Laboratory investigations revealed an activated partial thromboplastin time of 51 s (normal, 23-40 s), although it was normal during the 30th and 34th gestational weeks, LA with an anticardiolipin-beta2-glycoprotein I complex antibody, and low level of clotting XI activity (25 U/mL). On week 37 day 0 of gestation, the patient presented with severe hypertension. An urgent Cesarean section was performed after transfusion of two units of fresh frozen plasma. There was no excessive bleeding during the surgery or the postpartum period. The symptoms on her fingers and palms gradually improved after surgery. Our case indicates that dermatoses of pregnancy may become a starting point for the diagnosis of autoimmune diseases and coagulation abnormalities. When a patient presents with an atypical symptom, as in our case, the possibility of various diseases should be considered.