Objective To investigate the relationship between the 5-hydroxytryptamine (5-HT)1A receptor gene C(-1019)G polymorphism and geriatric depression and Alzheimer′s disease (AD) with depressive symptoms in Han Chinese. Methods The case control study was used in the study among 106 patients with geriatric depression, 72 AD patients with depressive symptoms and 150 healthy old individuals in China. The C(-1019)G polymorphism of 5-HT1A was analyzed with the technique of polymerase chain reaction-restriction fragment length polymorphism. Results The frequencies of 5-HT1A genotype C/G (39.6%), G/G(24.5%) and allele G (44.3%) in the patients with geriatric depression were significantly higher than those in the controls (respectively 35.3%, 13.3%, 31.0%, P < 0.05). The frequencies of 5-HT1A G allele in the AD patients with depressive symptoms (41.0%) were significantly higher than those in the controls (31.0%,X2=4.2879, P<0.05). No significant difference in distribution of (5-HT)1A C (-1019) G polymorphism between the patients with geriatric depression and the AD patients with depressive symptoms was observed (P > 0.05). Conclusion The 5-HT1A gene C (-1019)G polymorphism may be associated with geriatric depression and AD with depressive symptoms and (-1019)G allele may be a risk factor for them.