In this paper, the encapsulating effect of single molecule of zinc porphyrin (Zn−P) inside semiconducting single walled carbon nanotubes (NT17) on the stability and optoelectronic properties of organic solar cells is investigated, assuming that this nano‐hybrid system will serve as the active layer in solar cell device. Making use of density functional theory (DFT), we looked at the optoelectronic characteristics of the isolated Zn−P molecules as well as two different configurations of the hybrid system that has a single Zn−P molecule inserted into NT17 (Zn−P@NT17 and Zn−P2@NT17). The addition of a zinc atom at the core of a porphyrin molecule results in the emergence of novel electronic and chemical characteristics, leading to distinct behavior compared to a free‐base porphyrin. These distinctions hold substantial implications for a range of applications, encompassing catalysis, sensing, and energy conversion processes. According to the study's outcomes, a charge transfer (CT) between the Zn−P molecules and the NT17 nanotube caused the structure to remain stable, and assuming to the electronic and optical computations the CT in Zn−P@NT17 hybrid nanosystems has been identified, along with its orientation. The results show that type II heterojunctions on filled semiconducting carbon nanotubes are likely to make them a viable choice for charge and light transport in the active layer, which can help create filled NT‐based OSCs that are extremely efficient.