Thrombocytopenia is one of the critical parameters in patient management. Therefore, it is very important that laboratories assess platelet counts with utmost accuracy. Traditional microscopic methods are very intense with variable results and are highly dependent on the individual training. Recent developments in automated peripheral blood differentials using a computerized system have shown many advantages as a viable alternative. In reference to above context, this study was conducted with following objectives: To compare the estimation of platelet count done by manual method and by electrical impedance method in thrombocytopenic patient and asses the merits in clinical practice. This was a crossectional study carried out on 100 Patients with platelet count <1,50,000/cu mm over a span of 1 year. The platelet counts were done by automated analyser, using microscopy and on haemocytometer. Statistical software SPSS 2 and independent T tests were used to compare the variables between the groups. P value of <0.05 was considered significant. The overall mean platelet count by the electrical impedance method and manual method was 76.6 ± 34.7 x 109/L and 70.3 ± 36.93 x 109/L respectively. The P value for automated method versus manual method was 0.44,suggesting that there was no significant variation in the platelet counts between the manual methods when compared with the electrical impedance method. The study also inferred the method of manual counting using haemocytometer as preferable method of choice in case samples with very low platelet count on automated analyser using electrical impedance.