Despite the wide application of polycaprolactone (PCL) for bone tissue engineering application, its poor cellular interactions have resulted in the development of various strategies for surface modification. This paper established a surface modification approach based on gelatin immobilization on the PCL-3 wt. % diopside fibrous membrane. Moreover, the effects of swelling time on the amounts of immobilized gelatin were evaluated. Results demonstrated that gelatin was successfully immobilized within PCL-diopside membrane. Increasing swelling time from 5 to 30 min resulted in enhanced gelatin content. Moreover, while increasing swelling time upon 20 min did not significantly change the mechanical properties of gelatin-immobilized fibrous membranes, they reduced after 30 min swelling which might be due to the enhanced fiber and pore sizes as well as noticeably higher amount of immobilized gelatin within the membranes. Moreover, the hydrophilicity, biodegradation and bioactivity of PCL-3 wt. % diopside membrane significantly improved via gelatin immobilization. Finally, cellular behavior promoted because of the hydrophilic amino and carboxyl groups in the immobolized gelatin structure. Overall, our study suggested that gelatin immobilized PCL-diopside fibrous membranes could potentially be used to develop clinically revenant constructs for bone tissue engineering. (C) 2017 Elsevier B.V. All rights reserved.