The invention discloses an extracting and purifying process of pongamia pinnata flavonoids. The extracting steps of the process are as follows: step one, taking roots, stems and coarse leaf powders of pongamia pinnata, adding 50-70% of ethanol solution according to the proportion (mass per unit volume) being 8-15 times of medicinal materials, refluxing and extracting the mixture under 60-80 EDG C by three times for 0.5-2.0h each time, combining and filtering an extracting solution, and decompressing and recycling ethanol so as to obtain a pongamia pinnata flabonoid extracting solution; step two, standing the pongamia pinnata flabonoid extract solution obtained from the step one, taking supernatant and utilizing macroporous absorption resin for purifying the pongamia pinnata flabonoid, and eluting by ethanol; and step three, collecting ethanol eluent obtained from the step two, decompressing and recycling the ethanol for concentration, conducting vacuum drying under the temperature of 50-65 DEG C, and finally obtaining the purified object of an extract. In the process, the mass of total flavone accounts for 50%-70% in the extract of pongamia pinnata, and the transferring rate of the total flavone in the pongamia pinnata is 75-80%. Compared with the prior art, the extracting and purifying process has the advantages that the process is simplified, the loss of active ingredients is reduced, the safety is higher, and the like.