The present invention relates to an Internet-based small and public investment method, an investment profit distribution method, an investment loss prevention method through transition to real estate investment, and an investment method thereof. The method according to an embodiment of the present invention includes the steps of : inputting a superior deal with ensured profitability and stability to a purchase server; receiving investment applications; automatically classifying the form and method of the investment and calculating the confirmed investment amount to store the amount; notifying the transaction processing step to investors through text messages and emails on a real-time basis; finally requesting the investors to confirm the investment; and generating a legal contact and storing the contract.(5) Occurrence of hazardous elements(AA) Auction information of the Supreme Court(BB) Registering investment items(Bond/auction items)(CC) Starting investing bonds(DD) Bond group investment platform(EE) Applying for investment, Small amount, group investment(FF) Bond investing member(GG) Sole investment, Group investment, Price input law, Personnel appointment law, Account law, Small-amount investment law(HH) Second right analysis, Assets due diligence, Purchasing price negotiation(II) NPL purchase contract conclusion, Registration transfer(JJ) Miscarriage of auction, Risk occurrence of investment principal and profit, Determining to change to real investment(KK) Changing to real investment(LL) Member of real investment(MM) Real group investment platform(NN) Applying for investment, Small amount, group investment(OO) Successful bid(PP) Collecting the principal of real investment and the profit(QQ) Offset disposal of bond maximum price, Determination of approving the successful bid, Registration transfer, Disposal(RR) Collecting the principal of bond investment and the profitCOPYRIGHT KIPO 2015