The FUT3 gene encodes α(1,3/1,4)-fucosyltransferase, which is a crucial enzyme in the synthesis of Lewis antigens. FUT3 gene variants show race-specific differences. In this study, we conducted a systematic sequence analysis of the FUT3 coding sequence. The objective was to explore genetic variations of the FUT3 gene within the Han population of Northern China. A cohort of 313 blood donors was recruited for the study. The coding sequence of the FUT3 gene was amplified using polymerase chain reaction, followed by sequencing and haplotype construction. Twelve single nucleotide variations (SNVs) were identified within the coding sequence of the FUT3 gene. Notably, the c.59 T > G site exhibited the highest mutation frequency of 43.13%, followed by the c.508G > A and c.1067 T > A sites with mutation frequencies of 27.48% and 16.93%, respectively. Le was the most common haplotype, accounting for 67.57% of the cases, and Le/Le was the most common diplotype, accounting for 46.33% of the cases. The study also highlighted a significant difference in mutation frequencies of FUT3 gene between the Han Chinese of Northern China and the Dai of Xishuangbanna, China, but not the Han Chinese in Beijing in the North and the Southern Han Chinese, emphasising that Han Chinese in Northern China are genetically most distant from Europeans and closest to East Asians. Our study characterises FUT3 gene variations in Han Chinese from Northern China, and provides basic genetic data for genetics, forensic medicine, and genotyping of Lewis blood groups.