Disclosed is a risk assessment system for real estate lease deposits and a method thereof. The present invention comprises : a real estate database; a contract lease deposit input module for receiving a contractual lease deposit; an appropriate lease deposit estimation model setting up the scope of an area where the real estate belongs and selecting explanatory variables for estimating a tenancy deposit of the real estate by considering the scope of the set area, then generating an optimal lease deposit estimation model based on the hedonic price model by using selected explanatory variables, to estimate the appropriate lease deposit by the generated optimal lease deposit estimation model; an optimal selling price estimation module that selects explanatory variables for estimating an optimal selling price of the real estate, creates an optimal selling price estimation model based on the hedonic price model by using selected explanatory variables, and estimates an optimal selling price through the generated optimal selling price estimation model; a winning bid rate estimation module for selecting explanatory variables for estimating a winning bid price of the real estate, generating a winning bid rate estimation model based on a hedonic price model using selected explanatory variables, and estimating a winning bid rate through the generated winning bid rate model; a winning amount calculation module for calculating a winning bid price by multiplying the appropriate selling price and the winning bid rate; a residual dividend calculation module for calculating a remaining dividend from the winning bid amount; and a tenancy deposit risk diagnosis module for diagnosing and outputting the risk of contract lease deposit by comparing the contract lease deposit with the appropriate lease deposit and the remaining dividend individually. The present invention can automatically calculate the appropriate lease deposit for individual property without the help of an appraiser or lawyer, identifying the risk level of the lease deposit conveniently and accurately, by being configured to diagnose the possibility of recovering the lease deposit.(110) Real estate database(120) Contract lease deposit input module(130) Appropriate lease deposit estimation module(140) Lease deposit upper limit calculation module(150) Optimal selling price estimation module(160) Winning bid rate estimation module(170) Winning amount calculation module(180) Residual dividend calculation module(190) Estimated price adequacy reviewing moduleCOPYRIGHT KIPO 2017