Aim and Objective: Several plants from Lamiaceae family are used in the Saudi Arabia as a condiment and food preparation, and are generally used in the traditional preparation to treat various diseases, including anti-inflammatory, antioxidant, and microbial infections. Some of Lamiaceae species such as Mentha longifolia, Rosemarinus officinalis and Salvia officinalis having pharmacological active compounds such as α-pinene and eucalyptol. The aim of present study was to develop an accurate and precise chromatographic technique for quantification of α-pinene and eucalyptol in the Lamiaceae plants. Methods: The high-performance thin layer chromatography (HPTLC) method was developed as per International Conference on Harmonization (ICH) guideline. Results: Simultaneous determination of α-pinene and eucalyptol was achieved by developing a densitometric analysis of high-performance thin layer chromatography (HPTLC). Silica gel 60 F254 glass-backed plates (E-Merck, Germany, 0.2 mm layers) as stationary phase and mixture n-hexane: ethyl acetate 8 : 2 (%, v/v) as mobile phase were used to produce a sharp, symmetrical and well-resolved peak at an Rf value of 0.19 ± 0.02 and 0.52 ± 0.04 for α-pinene and eucalyptol, respectively. Linearly range for α-pinene was 100–700 ng/spot (r2 = 0.9988), whereas that for eucalyptol was 1000–7000 ng/spot (r2 = 0.9987). Conclusion: The developed method was found to be a simple, accurate, and precise, and it may be used to simultaneously analyses of many medicinal plants samples containing α-pinene and eucalyptol.