Objective：To investigate what factors could affect the accuracy of preoperative ^99m Tc-methoxy isobutylisonitrile(^99m Tc-MIBI) imaging in patients with secondary hyperparathyroidism(SHPT). Methods：The clinical characteristics of 482 renal SHPT patients undergoing surgical treatment in the First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed. Postoperative pathology was used as control，different imaging schemes(Group A：only ^99m Tc-MIBI dual-phase plane imaging；Group B： group A plus early phase SPECT/CT)were compared. In addition，patients in group B were divided into completely identified group and partly identified group，and the effects of clinical characteristics on MIBI imaging were analyzed. Results：In general，the sensitivity，specificity and diagnostic consistency of group B were higher than that of group A(81.9% vs. 70.3%；97.1% vs. 60.0%； 82.2% vs. 69.9%；99.9% vs. 97.9%，P ＜ 0.01 respectively). However，there was no significant difference in negative predictive value (6.8% vs. 10.2%，P ＞ 0.05). Serum phosphorus ion level was an independent risk factor for predicting false negative MIBI imaging (OR=0.57，95% CI：0.372~0.866，P=0.007). The risk of misdiagnosing on ^99m Tc - MIBI dual - phase plane imaging plus early phase SPECT/CT was increased when the level of serum phosphorus ion was lower than 1.97 mmol/L. Conclusion：^99m Tc -MIBI dual -phase plane imaging plus early phase SPECT/CT can improve the sensitivity and accuracy of hyperfunctional parathyroid tissue detection in SHPT patients. The judgment of imaging results should be combined with the level of serum phosphorus ion. When the level of serum phosphorus ion is lower than 1.97 mmol/L，imaging doctors and clinicians should concentrate on the possibility of misdiagnosing hyperfunctional parathyroid.