Dill seed is one of the important medicinal and aromatic crop. Dill variety GJ-1 was used as a raw material for extraction study. The different physico-chemical properties of essential oil, viz., specific gravity, optical rotation, refractive index, carvone content and suitability in alcohol were determined to evaluate the quality of essential oil. The treatments consisted of five levels of particle size i.e. whole dill, P1 (-8+20), P2 (-20+35), P3 (-35+65) and composite ground dill with five replications. The highest mean value of oil recovery (3.68g/100g) was observed in case of P3 with an effective experimental distillation time of 5.0 h. It was observed that specific gravity and refractive index of essential oil ranged 0.9521 to 0.9062 and 1.4933 to 1.4856 respectively. The lowest value was found in case of P3 particle size. It was found that the optical rotation decreased with decreases in particle size. The carvone content was higher in case of whole dill seed. The extraction of essential oil from dill seed by the method of water distillation should be carried with the ground dill having a particle size of P3 and 3.44 h of distillation time so as to get maximum recovery and best quality oil.