The carriers of the G allele and GG genotype in the SNP in KLK4 (rs198968) in the group with primary dentition were at a higher risk of dental caries compared to the carriers of the A allele and AA + AG genotypes, respectively (p = 0.043, OR = 1.78, 95% CI 0.98–3.24, and p = 0.019, OR = 2.28, 95% CI 1.11–4.69). Here, KLK4 is linked to dental caries.