The tubular structure is promising for use in hard template, microreactor, gas storage and sensors. Hollow Ag–POMs microtubule with diamond shape and hexagonal hole was successfully prepared by using a simple method from H3PW12O40 and AgNO3. The prepared sample was characterized by FTIR, scanning electron microscopy and EDS. For the prepared fibers with hollow structures, the length is about tens of micrometers, and both inner diameter and wall thickness are in the ranges of 0.5–1.0μm. The plausible reaction mechanism was proposed.