This study conducted through the tests of 9 interior slab-column joint specimens with partial utilization of ultra-high performance concrete (UHPC) under concentrated vertical loads to explore a new method for enhancing the punching shear resistance of such joints. This test examined the impact of UHPC on the performance and damage mechanisms of slab-column joints. The test parameters included the dimensions of the UHPC area as well as the volume fraction of steel fiber present in the UHPC. The test results indicated that UHPC had the potential to substantially enhance the ductility and punching shear capacity of slab-column joints. When UHPC was used locally in an area of one times the slab thickness from the column face, the ductility and punching shear capacity for specimens with a fiber ratio of 0.8% increased by 126% and 64%, respectively, compared to the specimens made entirely of normal concrete (NC). Therefore, the overall performance of the UHPC and NC composite slab-column joints can be enhanced with the rational UHPC area and volume fraction of steel fibers in practice. In this paper, the punching shear resistance of each specimen was estimated by three different codes. It was found that all the code equations either overestimated or underestimated the punching shear capacity within the UHPC region. Therefore, further research is necessary to explore the punching shear capacity of UHPC slabs. The finite element software ABAQUS was used to establish the force analysis model of specimens. The simulation results agree well with the experimental results. Based on this model, the effect of different UHPC area on the punching shear capacity of the specimens was further investigated. Finally, an empirical formula for estimating the punching shear capacity of UHPC–NC composite slab-column joints is proposed. The predicted values obtained from this formula show good agreement with the numerical results.