Despite low incidence of pregnancy-induced sacroiliitis, it is associated with significant morbidity and mortality. Sacroiliitis can be particularly difficult to diagnose because its symptoms are non-specific. A clinical case of postpartum sacroiliitis in a 24-year old patient is reported. The patient complained of severe right buttock pain radiating to the right thigh. In addition, the symptoms of systemic inflammatory response syndrome were present. Right-sided sacroiliitis was recognized by magnetic resonance imaging (MRI). Non-brucellar and non-tuberculous infectious sacroiliitis is a rare disease with misleading clinical signs that delay diagnosis. Most observations are based on individual case reports or small case series. Infectious sacroiliitis should be considered as a differential diagnosis even in low-risk women who present with debilitating pelvic pain during pregnancy and delivery. Thus, it may facilitate timely diagnosis and treatment.