Applications of nanomaterials to biological systems have received increased interest in the past decades. In particular, bacterial cellulose nanofibers can be utilized in a broad range of applications. Biomaterials have been produced on large-scale with high reproducibility by an inspiring method such as molecular imprinting. Herein, for the first time, magnetic bacterial cellulose nanofibers are designed by the molecular imprinting method as a novel adsorbent for selective and efficient recognition of thymidine nucleoside. In this process, magnetic bacterial cellulose nanofibers are silanized with 3-(trimethoxysilyl) propyl methacrylate and further polymerized with a hydrophilic monomer for templating thymidine via metal chelate coordination. They are characterized by several methods and then applied for thymidine recognition to optimize the adsorption conditions. Hereby, the effecting factors are evaluated, and the highest adsorption capacity is obtained as 431.3 mg/g in pH 9.0 at 25 degrees C. The selectivity is assessed with competitor nucleosides and highly selective (4.13 and 3.80 times) adsorption of thymidine at the same concentration of other nucleosides (cytidine and uridine) is observed. After multiple adsorption-desorption experiments, the magnetic bacterial cellulose nanofibers also provided high reusability capacity. The present new work holds excellent potential for nucleoside recognition by integrating molecular imprinting with magnetic bacterial cellulose nanofibers.