The invention relates to a method for preparing 8-hydroxyquinoline metal compounds, in particular to a synthesis method for organic electroluminescent materials. A method for the preparation of a compound of Mqnqm', in which M is Al, Li; n is 1 to 3, m is 0-2, q is 8-hydroxyquinoline and derivatives thereof, and q' is a ligand different from q, comprises the steps of: using a hydrophobic solvent, formulating industrial ligand to a solution for being dropped into a reaction vessel, stirring at certain temperature to obtain high-purity products. By using the hydrophobic solvent, the invention can implement the reaction efficiently, shorten reaction period, avoid complicated operation and purification procedures, enhance yield and purity of the product, reduce environmental pollution and lower the cost, besides, the resultant mother liquid can be reused. The technology can be popularized to the preparation of other 8-hydroxyquinoline metal compounds, and the resultant product can serve as an electroluminescent material or an electronic transmission material.