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Introduction. Unconventional starch sources are interesting industrial alternatives, each presenting different properties. Thermal, morphological, structural and pasting characteristics from ginger starch were investigated in this study. Materials and methods. Ginger starch was extracted by aqueous process and its characteristics were analysed by thermogravimetry/derivative thermogravimetry, differential scanning calorimetry, rapid viscoamylographic analysis, scanning electron microscopy and X-ray powder diffractometry. Results and discussion. Similar thermal stability and three mass losses were found for the starch samples. Higher transition temperatures and enthalpy of gelatinisation were found for commercial sample, which was related to the longer amylopectin chains due to B-type crystallinity. Starch obtained from "doce" ginger showed the highest peak and final viscosities associated with the lowest pasting temperature, which is a interesant result for food applications, in addition to the low energy required for gelatinisation. An ellipsoidal shape and no fissures on the surface of the granules were visuallised by microscopy, and the diameter and the commercial sample had the smallest granules. A-type diffraction was obtained for doce and "forte" ginger starches, while commercial starch presented B-type pattern. The highest relative crystallinity was exhibited by the "forte" ginger starch. Conclusions. Commercial samples presented differences compared to known varieties. Interesting properties were found, highlighting the "doce" ginger variety. [ABSTRACT FROM AUTHOR]