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We present detailed photometric observations of the Galactic globular clusterNGC 7492 using the data obtained with two far-ultraviolet (FUV: 1300 - 1800\AA) and three near-ultraviolet (NUV: 2000 - 3000 \AA) filters of UltravioletImaging Telescope (UVIT) on-board the \textit{AstroSat} satellite. We confirmedthe cluster membership of the extracted sources using GAIA data release 2 (GaiaDR2) proper motion data. We have used color-magnitude diagrams (CMDs) usingUVIT and GAIA filters to separate out different evolutionary stages of thestars present in the cluster. We have identified a new extreme horizontalbranch (EHB) star at the core of the cluster using UV and UV-optical CMDs. Theestimated distance-modulus of the cluster is $16.95\pm0.05$ obtained by fittingBaSTI isochrones with cluster parameters, $[Fe/H] = -1.8$ dex and age $= 12.0$Gyr on the V $-$ I vs V CMD. Interestingly, only the EHB star and bluehorizontal branch stars (BHBs) among the UV-bright hot sources are detected inFUV filters of UVIT. We have derived the effective temperature of BHBs usingcolor-temperature relation and spectral energy distributions (SEDs) ofmulti-band filters, which are in the range from 8,000 K to 10,500 K. We find avariation of He abundance of BHBs by fitting the BaSTI ZAHB. The range in theHe abundance of the BHBs corresponding to the best fit isochrones is 0.247 to0.350. We have estimated various physical parameters of the newly identifiedEHB star in the cluster using SED fit and post-HB evolutionary tracks. We havestudied the radial distribution of all the sources of the cluster detected inUVIT. The sources detected in FUV filters extend beyond the half light radius(1.15$'$) of the cluster, whereas the sources detected in NUV filters extendbeyond the tidal radius (9.2$'$) of the cluster.

Ultraviolet Imaging Telescope (UVIT) observation of the Galactic Globular Cluster NGC 7492