Unique coral-like silver citrate (Ag3C6H5O7, SC) microstructures (CSCM), with a surface roughened by numerous short needle points in a dense array, have been fabricated via a one-step strategy in aqueous solution for the first time. Time-dependent morphological evolution experiments revealed the growth process. The as-prepared CSCM with nanoscale roughness exhibited excellent performance and supersensitivity as a surface-enhanced Raman scattering (SERS) substrate, indicating potential application in SERS-related detection.