Lavender is a decorative, aromatic and medicinal plant which falls under the family of Lamiaceae (mints). It originates from the western part of the Mediterranean. It got its name from the Latin word lavare which means „to wash“. Its name explains the basic purpose of the dried flowers and the essential oils. In Croatia it is most commonly found on the islands of Hvar, Vis and Brač. In the past few years the cultivation of the plant has spread more towards the continental parts of Croatia and Istria. Lavender is grown because of the very valuable essential oil made by the distillation of the flower. Flower of the real lavender contains smaller percentage of essential oil (0.5 – 1.5 %) than the hybrid lavender (0.9 – 5 %). Essential oil of lavender is used in medicine, cooking, cosmetics and pharmaceutical industries. For the research purposes of this paper, the plants used were Lavandula angustifolia Hidcote and a hybrid kind of lavander, Lavandula x hybrida Budrovka. Their flowers were dried using the process of dehydration at three different temperatures (40 °C, 50 °C and 60 °C). The speed of releasing moisture from the flowers of lavender and lavandin were measured throughout the process of drying. The fastest drying was recorded at 60 °C. The amount of water, ash and fat contained in fresh and thermally processed flowers was compared. The amount of essential oils and herbal distillates in fresh and processed lavender and lavandin were determined using the method of steam distillation. Energy value was measured on the thermally processed stem and leaf of lavender and lavandin. The results of the research showed that the increase in temperature decreases the oil content in lavender flowers and lavandina flowers in relation to the fresh sample. Lavandin flowers had higher initial moisture (58.93%), while lavender flowers had lower initial moisture (67.36%).