The profile control and displacement technology using nanomaterials has outstanding advantages at the material scale，which has shown significant effects in pilot tests of representative blocks in different reservoirs. However，the unclear mechanism of the profile control and displacement system fundamentally hinders the large-scale application of the technology. In order to investigate the profile control and displacement effect and mechanism of two typical nanomaterials，nanoemulsion and nanosphere，carbonate reservoirs were taken as the research objects. The complexity of its pore structure was recognized based on the cast thinsection made from real cores，and three types of reservoir micromodels were designed and fabricated according to the characteristics，including pore-type，fracture-type，and vuggy-type reservoirs. Microfluidic experiments were carried out by using the profile control and displacement system in single and combined modes to obtain the images before and after the action and capture the microscopic phenomena during the profile control and displacement process. The profile control and displacement phenomena were combined with numerical change laws，and the effects of different profile control and displacement measures on increasing production in various carbonate reservoirs were discussed from the aspects of qualitative description and quantitative analysis. Meanwhile，the microscopic profile control and displacement mechanisms of the two nanomaterials were clarified. The experimental results show that using nanoemulsion and nanosphere for profile control and displacement can promote the effective mobilization of residual oil after water flooding in the three types of carbonate reservoir micromodels. Among them，the pore-type reservoir has the highest oil recovery；the fracture-type reservoir has the highest increase in production，while the vuggy-type reservoir has relatively poor performance. The nanoemulsion can improve the microscopic displacement efficiency by reducing the interfacial tension and changing the wettability to produce the remaining oil in the dominant flow area. The profile control and displacement effect of the nanosphere is mainly reflected in blocking the initial water flow channels to make the subsequent fluid turn into the unswept areas to further expand the swept areas.