Δ-Aminolevulinic Acid Dehydratase (ALAD) is an enzyme that encode heme biosynthesis by catalyzing the condensation of two molecules of Δ-Aminolevulinic Acid (ALA) to form a monopyrrole porphobilinogen (PBG) ring. This enzyme is encoded by the ALAD gene. The ALAD gene plays an important role in lead exposure, where lead entering the bloodstream can inhibit ALAD enzyme activity, thereby disrupting the heme biosynthesis pathway. Polymorphism in the ALAD gene can result in higher susceptibility to increased blood lead levels (BLL). The purpose of this study was to identify the polymorphism of the ALAD gene in workers exposed to lead from dyes. A total of 71 blood samples were isolated DNA, the continued amplification with PCR RFLM using Msp1. The presence of polymorphism was continued with DNA sequencing. The result of the study showed the frequency of ALAD-1, ALAD-1/2, and ALAD-2 genotype were 97,18%; 2,82%; and 0%. The sequencing result of the ALAD-1/2 genotype showed an allele change from 177G to 177C. The conclusion of this study that the genetic variation obtained from workers exposed to lead from dyes is more than 1%, so that it can be stated as a polymorphism.