Manipulated roughness has been etched on nanofibers to modulate adsorption of serum proteins for serum-free cells cultivation. Mixtures of Polycaprolactone and Pluronic with various blending ratios are electrospun to nanofibers and Pluronic is subsequently leached out by methanol. Electron microscopy reveals that surface roughness of the nanofibers is changed according to the contents of Pluronic. Both weight loss monitoring and NMR spectroscopy confirm that all Pluronic is leached out after methanol treatment. Water swelling ratio and protein adsorption of rougher nanofibers are higher than those of smoother ones. Also, when serum incorporation on the nanofibers is estimated in 0.01-10% serum solution, rougher nanofibers show higher serum incorporation and those soaked in 10% serum solution are employed for serum-free cell cultivation. Viability of the cells cultivated on rougher nanofibers is much higher after 24 h. Thus, Pluronic-induced leaching-out strategy can be potentially employed for fabricating roughness on nanofibers for enhancing protein adsorption for serum-free cell cultivation.