The aim of the experiment was to highlight the toxicity of the CrVI, administered during three generations, on the haemoglobin and on the osmotic resistance of the erythrocyte membrane in female rats. The determinations have been carried out on rat blood collected from female rats that reached sexual maturity, from F0, F1, F2 generation, exposed to LOAEL, of CrVI, as potassium dichromate, in drinking water (3 months). F1 and F2 were obtained from female rats from generation F0 and respectively F1 exposed for 3 months to chromium dose, mated with male rats exposed to the same dose for three months, before mating. The results of the experiment indicated a high significant decrease of haemoglobin, (p<0,01) under to the control lot and under physiologic limits, in the three generations. The decrease of hemoglobin, registered also high significant differences (p<0,01) as well between generation F0 and respectively generation F1 and F2. The chromium toxicity impact on erythrocyte membrane was shown by the progressive decrease of osmotic resistance even from the first generation and by the increase of the haemolysis degree in hypotonic solutions. The exposure to LOAEL CrVI during three generations produces toxic effects on erythrocytes inducing hemolytic effect.