Objective To investigate ultrasonography features of primary thyroid non-Hodgkin lymphoma (PT-NHL). Methods Ultrasonographic data of patients with PT-NHL(PT-NHL group) and non-Hodgkin lymphoma (control group) who were treated in our hospital from May. 2002 to Jul. 2014 were collected and analyzed. Results Compared with control group, enhancement of posterior echoes was more common in PT-NHL group (P=0.000), and difference values of transverse diameters, anteroposterior diameters, and sagittal diameters of more involved lobe to another lobe were bigger(P < 0.05), but echo pattern of gland, ultrasonographic classification of lesions, classification of vascularity, and condition of cervical lymph nodes were found no statistical difference(P > 0.05). In patients with nodular-type lesions(37 patients in PT-NHL group and 12 patients in control group), length of nodule lesions was larger in PT-NHL group (P=0.000), but there was no statistical difference in shape, boundary, orientation, and echoes of nodules between 2 groups(P > 0.05). In Pulsed-Wave(PW) Doppler between 2 groups(17 patients in PT-NHL group and 4 patients in control group), vascular resistance index(RI) was higher in PT-NHL group than those of control group (P=0.024). Conclusion The enhancement of posterior echoes was a feature in ultrasonography images of PT-NHL. Asymmetrical volume, high value of RI, and big nodule might link to PT-NHL, but diffuse heterogeneous echo with hypoechoic lesions might result in wrong diagnosis as PT-NHL.