To set a minimum order quantity of 1 piece on 1688 (Alibaba), follow the steps below:

Log in to your 1688 account and enter the seller's backend.

Select "Product Management" in the left menu bar.

Select the product on the page that needs to be set with a minimum order quantity of 1 piece, and click to enter the product editing page.

On the product editing page, find the "Sales Information" section, find the "Minimum Order Quantity" field, and fill in "1".

After confirming that the entry is correct, click the "Save" button to save the settings.

After completing the above steps, the product can be sold with a minimum order quantity of 1 piece. It should be noted that different products may have different settings. For specific operations, please refer to the 1688 seller manual or consult 1688 customer service.