The judgment of the court below is reversed, and the case is remanded to Suwon District Court Panel Division.

The grounds of appeal are examined.

1. Review of the reasoning of the lower judgment and the record reveals the following facts.

(1) On November 29, 2013, the Plaintiff subcontracted part of the instant construction work to F Co., Ltd. (hereinafter “F”) on February 17, 2014 (the total sum of KRW 676,500,000, labor cost of KRW 348,500,000, value-added tax of KRW 102,50,000).

(2) Article 22(1) of the subcontract agreement provides that the Plaintiff shall pay advance payment to F. Article 22(5) of the subcontract agreement provides that the advance payment shall be made according to the formula of “amount of advance payment 】 amount equivalent to the price of the completed portion ± contract amount” ± the settlement of the advance payment according to the formula of “contract amount.”

(3) In order to guarantee the repayment obligation of advance payment owed by F to the Plaintiff upon occurrence of the cause for termination, etc. of the subcontract, the Defendant issued to the Plaintiff an advance payment guarantee amount of which F is the Plaintiff, which is KRW 189,750,00 on February 19, 2014, with the guarantee amount of KRW 744,150,00, the contract amount of KRW 127,50,000, the contract amount of KRW 1,127,50,000, and the guarantee period from February 19, 2014 to December 4, 2014.

(4) Article 2(1) of the Terms and Conditions for Advance Payment stated on the back of the letter of advance payment guarantee provides that “The advance payment settlement shall be made in accordance with the method of settlement specified in the main contract, and if the main contract (or, in the case of a subcontract, the superior construction) is an annual construction contract (including a long-term continuing construction and continuing expenditure contract), the advance payment settlement shall be made on the basis of the contract amount subject to advance payment (the contract amount as the basis for advance payment calculation).”

(5) On February 19, 2014, the Plaintiff notified F that it would pay KRW 189,750,000 as an advance payment under the subcontract agreement, and paid the said amount to F as an advance payment.

(6) As F did not properly perform its obligations under the subcontract after the subcontract, the Plaintiff notified the termination of the subcontract to F on October 6, 2014, and the notification is F.