Objective:To evaluate the correlation between the expression of somatostatin receptor(SSTR) in tumor tissue and the 99mTc-acetate-octreotide scintigraphy of non-small cell lung cancer(NSCLC). Methods:Nude mice bearing human NSCLC model were established. 99mTc-acetate-octreotide imaging was performed in NSCLC model, and the ratio of tumor to normal tissue(T/NT) was calculated over ROI to observe the radioactive uptake. The biodistribution was studied. The mRNA expression of SSTR in tumor tissue was detected by RT-PCR to evaluate the correlation between the expression of SSTR in tumor tissue and the 99mTc-acetate-octreotide scintigraphy of NSCLC. Results:Static planar image showed that the tumor had focal uptake of 99mTc-acetate-octreotide. Four hours after 99mTc-acetate-octreotide administration,the T/NT ratio was 2.38 ± 0.09. The biodistribution showed high uptake of the tracer in tumor;high expression of SSTR3 and SSTR5 in NSCLC,especially SSTR5. Positive correlation were obtained between the T/NT ratio and the expression of SSTR5 mRNA(r = 0.93,P < 0.01). Conclusion:SSTR3 and SSTR5 are highly expressed in NSCLC cell line, especially SSTR5. There is a significant correlation between the tumor uptake of 99mTc-acetate-octreotide and SSTR5 mRNA expression. This approach may provide a basis for SSTR targeted diagnosis and therapy of human NSCLC.