BackgroundMalaria is a worldwide infectious disease. For countries that have achieved malaria elimination, the prevention of re-establishment due to infections in returned travellers has become important. The accurate and timely diagnosis of malaria is the key in preventing re-establishment, and malaria rapid diagnostic tests (RDTs) are frequently used due to their convenience. However, the RDT performance inPlasmodium malariae (P. malariae)infection diagnosis remains unknown.MethodsThis study analysed epidemiological features and diagnosis patterns of importedP. malariaecases from 2013 to 2020 in Jiangsu Province and evaluated the sensitivity of four parasite enzyme lactate dehydrogenase (pLDH)-targeting RDTs (Wondfo, SD BIONLINE, CareStart and BioPerfectus) and one aldolase-targeting RDT(BinaxNOW) forP. malariaedetection. Furthermore, influential factors were investigated, including parasitaemia load, pLDH concentration and target gene polymorphisms.ResultsThe median duration from symptom onset to diagnosis among patients withP. malariaeinfection was 3 days, which was longer than that withPlasmodium falciparum(P. falciparum) infection. The RDTs had a low detection rate (39/69, 56.5%) amongP. malariaecases. All tested RDT brands had poor performance inP. malariaedetection. All the brands except the worst-performing SD BIOLINE, achieved 75% sensitivity only when the parasite density was higher than 5000 parasites/μL. Both pLDH and aldolase showed relatively conserved and low gene polymorphism rates.ConclusionsThe diagnosis of importedP. malariaecases was delayed. The RDTs had poor performance inP. malariaediagnosis and may threaten the prevention of malaria re-establishment from returned travellers. The improved RDTs or nucleic acid tests forP. malariaecases are urgently needed for the detection of imported cases in the future.