We report a case of a 58-year-old Caucasian woman affected by papillary thyroid microcarcinoma (PTMC) of the left-lobe of the gland with very small size (Ø 0.3 cm). The characteristics with the Diagnostic Imaging using Ultrasonography, ADF (Advanced Dynamic Flow), and fine-needle-aspiration cytology (FNAC) are discussed, comprising a very small micro-focus of radial shape, with markedly hypoechoic echostructure, irregular margins, supplemented by peripheral vessel formation. It acquires an image which appears similar to a brisk visualization of a dark ink stain in the normal thyroid weave. We call such a pattern "Black Ink" with ultrasonographic image and believe consistent with the infiltrating variant of papillary thyroid microcarcinoma if associated with malignant cytology after FNA.