Introduction: The first cases of Y chromosome microdeletions and male infertility were reported in 1992 and many case series have subsequently been reported from various parts of the world. A very few studies have been done involving the patients of North-East Indian states, so this study aimed to detect frequency and incidence of AZF microdeletions in this population with special reference to AZFa and AZFd region of long arm of Y chromosome. Aims: The main objectives involve - a) Determination of microdeletion frequency for each type of infertility group included in the study. b) Determination and comparison of the microdeletion frequency of Y chromosomal AZFa and AZFd region in the cases using 2 gene-specific markers: USP9Y, DBY and 3 STS markers: sY145, sY152, sY153. c) Evaluation of the importance of using markers, not specified by European Academy of Andrology (EAA) to detect Y chromosome microdeletion, in Indian scenario. Methods: A total of 170 infertile males attending private infertility clinics of Guwahati, Assam were selected for the study. This includes 50 azoospermic, 82 oligozoospermic, 18 oligoasthenozoospermic and 20 asthenozoospermic cases. Both blood and semen samples were collected from 45 individuals. PCR amplification was carried out using specific primer sets and isolated genomic DNA. All genes and STS markers were amplified efficiently in samples from 50 fertile men tested, but failed to be amplified in samples from fertile women. Results: The frequency of Y chromosome microdeletion with respect to AZFa and AZFd region was found to be 25.3% (43/170). In azoospermic, oligozoospermic, oligoasthenozoospermic and asthenozoospermic cases it was found to be 28% (14/50), 26.8% (22/82), 11.1% (2/18) and 25% (5/20) respectively. In the cases with single marker microdeletion, microdeletion of only DBY gene was found to be associated with all the four infertility groups. In the 45 individuals from whom both blood and semen samples were available, frequency of Y chromosome microdeletion was found to be higher in semen samples (20%) than blood (17.8%) samples. Conclusion: It shows that markers not specified by EAA are also good enough in determining Y chromosome microdeletion in the present population. We also suggest that the use of DNA isolated from semen sample, for Y chromosome microdeletion screening can be a better option as it can detect the deletions not detected by blood sample analysis.