Cromolyn sodium (CS), a mast cell stabiliser, is widely employed for the prevention and treatment of allergic conditions. However, high hydrophilicity and poor oral permeability hinder its oral clinical translation. Here, solid lipid nanoparticles (SLNs) have been developed for the purpose of oral bioavailability enhancement. The CS-SLNs were engineered by double emulsification method (W-1/O/W-2) and optimised by using Box-Behnken experimental design. The surface and solid-state characterisations revealed the presence of CS in an amorphous form without any interactions inside the spherical-shaped SLNs. The in-vitro release study showed an extended release up to 24hr by diffusion controlled process. Ex-vivo and in-vivo intestinal permeation study showed approximate to 2.96-fold increase in permeability of CS by presentation as SLNs (p<0.05). Further, in-vivo pharmacokinetic study exhibited approximate to 2.86-fold enhancements in oral bioavailability of CS by encapsulating inside SLNs, which clearly indicate that SLNs can serve as the potential therapeutic carrier system for oral delivery of CS.