Background: Thyme (Thymus vulgaris L.) is an aromatic and medicinal plant of Lamiaceae family which cultivated in different region of Iran. Objective: Evaluation of methanol and ethanol spraying effects on dry matter and phytochemical yield of thyme (Thymus vulgaris L.). Methods: This study was done in a randomized complete block design with three replications and eleven treatments in the research farm of ACECR - Institute of Medicinal Plants in Karaj, Iran. The treatments were: control (without spray), ethanol solutions with 10, 20, 30, 40 and 50% (v/v) and methanol solutions with 10, 20, 30, 40 and 50% (v/v). The volatile oil was extracted by hydrodistillation using Clevenger-type apparatus then after it was analyzed by GC and GC/MS. Results: The results showed that the foliar application of hydro-alcohols treatments had significant effect (p<0.01) on all studied parameters. The highest dry matter yield was obtained at methanol 30% and ethanol 20%. Also, the highest yield of oil, thymol and carvacrol was observed at 20% methanol, 10 and 20% ethanol, respectively. Conclusion: Foliar application of methanol and ethanol increased the yield of dry matter and content of volatile oil, thymol and carvacrol.