Objective To get the high quality and high yield of total DNA from Panacis majoris. Methods Used the methods CTAB， improved CTAB， SDS and high salt low PH extraction the total DNA， The quality of the DNA was examined with spectrophotometer and agarose gel electrophocesis. Results The results showed that the highest yield was CTAB， productive rate is 149. 533ng/g， the best quality is improved CTAB， OD260/OD280 IS 1. 796. Conclusion The total DNA from the four extraction methods， all can used the SSR marker， the best effect was improved CTAB and the SDS.