The main objective of this study was to develop solid self-nanoemulsifying drug delivery system (S-SNEDDS) of Irbesartan (IRB) for enhancement of its solubility and dissolution rate. In this study, a novel liquid SNEDDS containing Irbesartan was formulated and further developed into a solid form by spray drying technique using Aerosil 200 as solid carrier. The solubility of IRB was determined in various oils, surfactants and co-surfactants to select the best candidates for IRB for further study. Pseudoternary phase diagrams were constructed to identify the efficient area of self-nanoemulsification. Based on preliminary screening of different unloaded SNEDDS formulae, eight formulae of IRB loaded SNEEDS were prepared using Capryol 90, Cremophor RH40 and Transcutol HP as oil, surfactant and cosurfactant respectively. The optimized IRB loaded SNEDDS formulae were evaluated for effect of dilution (with different volumes at different pH values), efficiency of self-emulsification, viscosity, optical clarity, morphological characterization, drug loading efficiency, in-vitro drug release, droplet size analysis as well as polydispersity index (PDI). SNEDDS formulae were also tested for thermodynamic stability and zeta potential to confirm the stability of the prepared SNEDDS. Results showed that the mean droplet size of all reconstituted SNEDDS was found to be in the nanometric range with optimum PDI values. All formulae also showed rapid emulsification time, good optical clarity, and high drug content; and found to be highly stable. Transmission electron microscopic images showed the formation of spherical and homogeneous droplets with a size smaller than 50nm, which satisfies the criteria of nanometric size range required for nanoemulsifying formulae. In-vitro release of IRB from SNEDDS formulae showed that more than 99% of IRB release in approximately 90 minutes. Optimized SNEDDS formulae with the smallest particle size, rapid emulsification time, best optical clarity, and maximum drug content and rapid in-vitro release were selected to be developed into solid self-nanoemulsifying drug delivery system (S-SNEDDS) using spray drying technique. The prepared S-SNEDDS formulae were evaluated for flow properties, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), reconstitution properties, drug content and in-vitro dissolution study. It was found that S-SNEDDS formulae showed good flow properties and high drug content. Reconstitution properties of S-SNEDDS showed spontaneous self-nanoemulsification and no sign of phase separation. DSC thermograms revealed that IRB was in solubilized form and FTIR supported these findings. SEM photographs showed smooth uniform surface of S-SNEDDS with less aggregation. Results of the in-vitro drug release showed that there was great enhancement in dissolution rate of IRB.