This study investigates the impact of the scale-aware convective parameterization scheme (CPS) on convective cells related to simulation of heavy precipitation across the gray-zone using the Weather Research and Forecasting (WRF) model. We select the Kain-Fritsch (KF) and Multi-scale Kain-Fritsch (MSKF) schemes as non-scale-aware and scale-aware CPSs, respectively. The MSKF scheme uses a scale-aware parameter that modulates the convective available potential energy (CAPE) timescale and entrainment process in the KF scheme as a function of the horizontal grid spacing. This study shows that simulation of convection only with grid-scale process microphysics parameterization scheme (MPS) (i.e., explicitly resolved) causes an unreasonably overestimated and erroneous location of precipitation in the gray-zone because convection and atmospheric instability could not properly be triggered and reduced. Contrarily, the CPS without scale-awareness in the gray-zone exaggerates the convection and distorts synoptic fieldsleading to the erroneous simulation of heavy precipitation at high resolution. Contrastingly, the MSKF scheme with scale-awareness improves simulated convective cells related to heavy rainfall by removing atmospheric instability in the gray-zone, smoothly reducing the role of CPS and increasing the role of MPS as grid spacing is decreased. Additionally, the sensitivity experiments show that the shorter CAPE timescale and decreased entrainment process resulted in fast development and exaggeration of convective activities, respectively. These parameters modulated by the scale-aware MSKF scheme can play a crucial role in the balanced effect between the CPS and MPS in the gray-zone by controlling the entrainment rate and CAPE timescale.