We have used atom probe tomography (APT) to characterize the clustering behavior related to the bake-hardening (BH) response in an Al-0.62Mg-0.93Si (mass％) alloy during pre-aging (PA) at 363 K for 18 ks and subsequent natural aging (NA) after solid solution treatment.It can be seen that increasing NA time beyond 1.5 x 103 ks after PA causes a gradual increase in hardness.The material after PA followed by NA for 4.0 x 104 ks shows almost the same hardness after the BH treatment at 443 K for 3.6 ks as the PA material, namely, the long-term storage at room temperature after PA deteriorates the BH response.