2,4-Dichlorophenoxyacetic acid (2,4-D), which is a plant auxin analogue, is lethal to broad leaved Weeds,within days at high dosages and is considered as having low toxicity to mammals. Some studies have reported that exposure to this compound may cause damage to organs such as liver. The aim of this study was to investigate the effects of 2,4-D in mouse liver on chromosomes as well as hexokinase (HK), glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) which are required for the generation of the pyridine nucleotide pool. The experiments were carried out with a 2,4-D group, an ethanol control for 2,4-D, and saline group for ethanol control group on three generations of mice. Only female parents were given 2,4-D during the gestation period, lactation period and for 33 days following the lactation period. In females of the first cross, 2,4-D caused a significant increase in the activity of LDH, and ethanol alone caused a significant increase in the activities of HK and LDH. In the male offspring of the first cross maternal, 2,4-D caused a significant increase in the activity of LDH, and ethanol alone caused a significant decrease in the activity of 6PGD. In the female offspring of the first cross maternal, ethanol caused a significant increase in the activities of G6PD and MDH. In the female offsprings of the third cross maternal, 2,4-D caused a significant increase in the activity of MDH. No gross morphological changes were observed in internal organs, such as liver, kidney and spleen of the affected animals. Also, a chromosomal study from bone marrow cells indicated no anomalies in chromosomal sets and structures. As a result, 2,4-D had an effect on the first cross maternal and their offsprings. The compound did not affect the parameters studied except MDH enzyme activity in the second and third generation of mice.