<h2>Summary</h2> CO<sub>2</sub> reduction and fixation products, ranging from small molecules to biomolecules, are highly diverse in natural systems. Although various multicarbon products of CO<sub>2</sub> reduction were artificially obtained, the C<sub>3+</sub> products with various functional groups (e.g., C–N and C–O bonds), especially biomolecules, have never been reported. Herein, we synthesized C<sub>3+</sub> amino acids via electrocatalytic synthesis from CO<sub>2</sub> and NH<sub>3</sub>, using chiral Cu films (CCFs) as electrodes. Electron microscopy and theoretical calculations suggested that chiral kink sites can possibly be formed on the surface of CCFs fabricated through electrodeposition in the presence of histidine (His). Serine (Ser), with an enantiomeric excess (ee) greater than 90%, is the main component of various amino acids. Experimental and computational data showed that the 3-hydropyruvic acid formation from H<sub>2</sub>CO–CO∗ is the stereo-determining step in the Ser formation pathway. The chiral kink sites were speculated to be restricting the configuration changes of C<sub>3+</sub> intermediates to involve a thermodynamically and kinetically favorable formation of enantiomeric Ser.