We investigated anti-annexin V antibody (aANX) in patients with systemic lupus erythematosus (SLE), and correlated to positivity with lupus anticoagulant (LA)/anticardiolipin antibody (aCL). aANX was positive in 12/47 SLE patients (26%), including 7 with beta 2-glycoprotein 1 (GPI)-dependent aANX. The positivity of aANX was higher in patients with aCL (19%) and LA/aCL (50%) than in those without LA/aCL (10%). From these results, it is concluded that aANX is an autoantibody closely related to LA/aCL, and can be a possible new risk marker for thrombosis.