A structure and method for retaining fastening element solder are introduced. The structure includes a fastening element which has a solderable surface and a fastening portion or a hole portion. One end of the hole portion or the fastening portion has a retaining portion. During a soldering heating process, solder flows into or enters the retaining portion to cool down and solidify. The solidified solder is retained in the retaining portion. The fastening element is firmly coupled to a first object because of coordination between the solderable surface and the retaining portion, and the second object is coupled to or removed from the fastening element because of coordination between the fastening portion and the hole portion, so as to couple together and separate the first and second objects repeatedly and quickly.