Objective To investigate the application value of ultrasound-guided Encor system in minimally invasive surgery for nonpalpable breast tiny lesion resection． Method Four hundred and thirteen nonpalpable breast tiny lesions of 189 female patients were excised by the application of high-frequency color Doppler ultrasound guided real-time monitoring Encor vacuum assisted minimally invasive cutting system in minimally invasive surgery． Ｒesults All of the nonpalpable breasttiny lesions of 189 case patients were completely resected． Intraoperative pain can be managed，VAS score was below 3 points in all patients，and no skin miscut was reported． There was no postoperative infection，breast deformation，or obvious scar formation， and all patients indicated satisfaction． High-frequency color Doppler ultrasound 3 months after showed no mass residue． The incidence rate of intraoperative bleeding，postoperative hematoma，subcutaneous ecchymosis were 5． 61%，11． 21%，and 5． 61%，respectively in the group with ≤3 tiny lesions in 107 patients，and 8． 54%， 19． 51%，and 32． 92%，respectively in the group with ＞ 3 tiny lesions in 82 patients，the differences were all statistically significant ( all P ＜ 0． 05) between the two groups． All the hematoma and subcutaneous ecchymosis were absorbed and disappeared during the follow-up of 3 months． Conclusion High frequency ultrasound-guided Encor system in minimally invasive surgery has many superiorities such as accurate locating， high complete resection rate，smaller scars，no breast deformation，etc． It can be used as preferred surgical approach for the benign nonpalpable breast tiny lesions excision．

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