The NGVS-IR project (Next Generation Virgo Survey -Infrared) is a contiguous near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). The current state of NGVS-IR consists of K s -band imaging of 4 deg 2 centered on M87, and J and K s -band imaging of ∼ 16 deg 2 covering the region between M49 and M87. In this paper, we present the observations of the central 4 deg 2 centered on Virgo's core region. The data were acquired with WIRCam on the Canada-France-Hawaii Telescope and the total integration time was 41 hours distributed in 34 contiguous tiles. A survey-specific strategy was designed to account for extended galaxies while still measuring accurate sky brightness within the survey area. The average 5σ limiting magnitude is K s = 24.4 AB mag and the 50% completeness limit is K s = 23.75 AB mag for point source detections, when using only images with better than 0.7 seeing (median seeing 0.54 ). Star clusters are marginally resolved in these image stacks, and Virgo galaxies with µ Ks 24.4 AB mag arcsec −2 are detected. Combining the K s data with optical and ultraviolet data, we build the uiK s color-color diagram which allows a very clean color-based selection of globular clusters in Virgo. This diagnostic plot will provide reliable globular cluster candidates for spectroscopic follow-up campaigns needed to continue the exploration of Virgo's photometric and kinematic sub-structures, and will help the design of future searches for globular clusters in extragalactic systems. We show that the new uiK s diagram displays significantly clearer substructure in the distribution of stars, globular clusters, and galaxies than the gzK s diagram -the NGVS+NGVS-IR-equivalent of the BzK diagram, which is widely used in cosmological surveys. Equipped with this powerful new tool, future NGVS-IR investigations based on the uiK s diagram will address the mapping and analysis of extended structures and compact stellar systems in and around Virgo galaxies.