Anemia and particularly iron deficiency anemia is one of the most important factors in growing problems in puppies. It can make a lot of negative effects in growing process. Iron deficiency anemia is produced by depletion of iron reserves. Due to this depletion, no iron is available for haemoglubin (Hb) synthesis. Iron reserves depletion happens when the iron consumption or iron loss is considerably, more than synthesis. In this study two groups of puppies (25 puppies in each group) with 3 months old in average, were selected randomly. The first group was considered as the control group and the puppies of this group were fed with maternal milk. The second group was the test group and the puppies of this group were separated from their mother maximum at two weeks old. These puppies were fed manually with the cow's milk. One ml of blood was collected from each puppy and haematological factors such as red blood cells count (RBCC), Haemoglubin concentration (Hb), Hematocrit (PCV) and cellular indexes of MCHC, MCH and MCV were measured. The result showed that there is significant difference in "mean red blood cells count" between control and test groups. (P<0.05) Differences of "MCHC" between these two groups were also significant (P<0.05). More ever all of these parameters were compared statistically with their corresponding standard values and all differences were significant except for "MCHC" and "MCV" between control group and relevant standard values. It means that the RBCC in puppies fed with maternal milk are normocytic-microchromic and somehow iron deficiency in this group of puppies can be neglected. In other hand, "MCV" in test group had significant difference with normal values, so in this group the RBCC are microcytic-normochromic and this issue can be early stage of iron deficiency anemia.