Quantitative Structure Activity Relationship (QSAR) analysis of receptor binding affinity of progestagens with electrotopological state atom index (ETSA) has been performed in an attempt to locate the pharmacophore fragment of the molecules. The index has been projected to have potential to determine pharmacophore moieties of biologically active congeneric compounds. The study reveals the importance of C19 (attached to C13 atom), C3 (ring A), C9 and C10 atoms for mapping to the receptor binding. The importance of these atoms or fragments were also supported from previous reports. Thus, diagnostic potential of the ETSA scheme in identifying the atoms or fragments important for, binding affinity was revealed from the study.