The research's main objective was to improve bosentan solubility by preparing nanoemulsion (NE) for pulmonary artery hypertension therapy. Oleic acid was selected as oil, Tween 20 as a surfactant, and PEG600 as a co-surfactant. From the pseudo ternary phase diagram ratio of Smix (1:1) selected. From the ternary diagram's NE area, different batches were prepared. The optimized formulation NE F3 contains oil (5% w/w), Smix (50%w/w), and water (44.9% w/w). The prepared was evaluated for globule size 141 nm, 99% drug content. The physicochemical parameter of NE F3 was performed, and to enhance the stability of NE, it is converted into gel, by using Carbopol 934 and Xanthan gum. The in vitro drug release investigation after 8 hours % cumulative drug release (CDR) of NE gel was 88.3 ± 0.18%, and aqueous drug emulsion (F3) shows 40.8 ± 0.13%., which indicates that NE gel revealed better drug release than NE. There was increase in solubility compare to other formulations of drug. Keywords: Nanoemulsion, transdermal gel, pseudo ternary phase diagram, in vitro drug release