Niosomes are vascular systems used as safe and useful carriers for delivering both hydrophilic and hydrophobic drugs. These vesicles are considered as drug delivery systems, which are designed using non-ionic surfactants. Niosomes are designed by mixing of biocompatible and biodegradable non-ionic surfactant (usually spans and tweens) and cholesterol with dispersion in aqueous media. It is composed from a bilayer of non-ionic surfactant with two extents, one of them is hydrophilic and the other is hydrophobic. The purpose of the present study is to prepare diphenhydramine HCl (DPH HCl) proniosomal gel that is capable to convert into niosomal forms on hydration and delivering drug in extended time. Proniosomal loading DPH HCl formulas were prepared by coacervation method. Sorbitan esters (Span 20, Span 40, Span 60, and Span 80) and their ethoxylated derivatives (Tween 20, Tween 40, Tween 60, and Tween 80) were used in the preparation of proniosomal formulations. The prepared formulations were evaluated for physical manifestation, pH, shape, vesicles size, entrapment efficiency (EE), and in vitro drug release. Fourier-transform infrared (FT-IR) spectroscopy was used to examine the compatibility between medicine and other ingredients. Results showed that the most prepared niosomal formulations were in the nanosize range and exhibited uniformity in the sizes of the vesicles with higher EE (68.6%–97.83%). FTIR studies indicated that there was no interaction between DPH HCl and other formulation materials of niosomal formulations. The prepared formulations containing Tween surfactants revealed higher release rates when compared with Span formulations. According to the results, niosomal formulation could be formulated for DPH HCl as transdermal delivery system. The above results indicated that DPH was well prepared as proniosomal gel with high EE using coacervation technique. Proniosomal formulation as a drug delivery system seems to be possible with DPH HCl and could act as alternative for delivering the drug with prolonged release at the site of action, in addition to avoid the side effects of drug by the other routes of drug administration.