Amicrowave–assisted extraction procedure was optimized for the extraction of total phenols from rosemary(Rosmarinus officinalisL.) leaf in order to achieve the highest efficiency in this study. Effects ofmaterial particle size,ethanolconcentration,temperature,extraction time and solid–liquid ratio on the yield of total phenols from rosemary leaf usingmicrowave–assisted extraction were investigated by single–factor experiment.And then the optimization ofmicrowave–assisted extraction was performed using orthogonal experimental design princip...