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High-resolution imaging is crucial for exploring the origin and mechanism ofradio emission in quasars, especially at high redshifts. We present 1.5 GHzVery Long Baseline Array (VLBA) images of the radio continuum emission from theradio-intermediate quasar (RIQ) J2242+0334 at $z = 5.9$. This object waspreviously detected at both 1.5 GHz and 3 GHz with the Karl G. Jansky VeryLarge Array (VLA) as a point source. However, there is no clear detection inthe VLBA images at both the full resolution of 10.7 milliarcsecond (mas)$\times$ 4.5 mas (61.7 pc $\times$ 26.0 pc) and a tapered resolution of 26 mas$\times$ 21 mas (150 pc $\times$ 121 pc). This suggests that the radio emissionfrom the quasar is diffuse on mas scales with surface brightness fainter thanthe $3\sigma$ detection limit of 40.5 $\mu \rm Jy \ beam^{-1}$ in the fullresolution image. The radio emission in the RIQ J2242+0334 is likely to bewind-like (i.e., diffuse) rather than in the form of collimated jets. This isdifferent from the previous radio detections of the most luminous quasars at $z\sim$6 which are usually dominated by compact, high brightness temperatureradio sources. Meanwhile, compared with RIQs at low redshifts, the case ofJ2242+0334 suggests that not all RIQs are beamed radio-quiet quasars. Thisoptically faint RIQ provides an important and unique example to investigate theradio activity in the less powerful active galactic nuclei at the earliestcosmic epoch.

VLBA reveals the absence of a compact radio core in the radio intermediate quasar J2242+0334 at z =5.9