Concentrated microemulsions comprising: 1) 10-25 parts by weight of a pesticide with a solubility in water 20° C. lower than 1% by weight and having a melting point from 10° C. to 60° C.； 2) 8-25 parts by weight of one or more solvents containing oxygen atoms, having a solubility in water at 20° C. lower than 5% by weight and the Hildebrand solubility parameter in the range 16-21 MPa1/2: 3) 10-20 parts by weight of a polyol； 4) 10-25 parts by weight of one or more non ionic surfactants having a HLB value from 9 to 15； 5) 2-10 parts by weight of one or more anionic surfactants: 6) water up to 100 parts by weight； wherein&mdash；the ratio by weight between 2) and 1) ranges from 0.8:1 to 1.5:1；&mdash；the ratio by weight between 4)+5) and 1) is in the range 0.5:1-3:1；&mdash；the ratio by weight between 4) and 5) ranges from 1:1 to 4.1.
