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conversion efficiency (PCE) has already exceeded 16% enabled by advanced photovoltaic materials. [3][4][5][6] Although opaque OSCs exhibit high efficiency, their usage is limited because they demand dedicated space and additional installation work on the roof, like traditional silicon solar cells. Therefore, the transparent property of OSCs was exploited for semi-transparent photovoltaic modules to extend their application in power-generating windows for buildings and automobiles. To fabricate efficient semi-transparent OSCs (STOSCs) with high average visible transmittance (AVT), [7] several approaches have been attempted for improving the visible light transparency of active layer, including molecular energy level modulating in non-fullerene acceptors, [8][9][10][11][12] usage of low-band gap organic semiconductors to shift absorption to near-infrared region, [13] fabrication of active layer with fiber network structure [14] and so on.On the other hand, developing transparent electrodes (TEs) with high conductivity to reduce the absorption/reflection in visible light without degrading interfacial contact is also equally important to achieve high-performance STOSCs. [2] Evaporated thin metal-based top electrodes were most reported to date due to their high conductivity and transparency. [15][16][17] However, the high cost and strict conditions of vacuum-deposited TEs are not suitable for large-area device fabrication and contradict the aim of renewable energy. [18] Furthermore, the transmittance of evaporated thin metal is not uniform throughout the visible region, resulting in low color-fidelity in STOSCs. [19] Therefore, in the past decade, scientists have advocated to develop solution-processed TEs, such as conducting polymers, [20][21][22] Ag nanowires (AgNWs), [23][24][25][26] graphene, [27][28][29][30] and carbon nanotubes (CNTs). [31][32][33][34] Nonetheless, the sheet resistance of polymers-based and carbon-based TEs is relatively high and even the lowest reported values to date is larger than 50 Ω sq −1 . Moreover, the acid treatment at high temperature for the conductivity enhancement of polymers adversely damages the underlying layers of OSC, [35][36][37] and hence complicated transfer process is required to be used as top TEs. [38,39] In addition, the unsatisfactory vertical conductivity of carbon materials and the stability issue of AgNWs and conducting polymers make them unappealing to be used in STOSCs. Semi-transparent organic solar cells (STOSCs) have attracted tremendous attention in power-generating windows for buildings and automobiles.Although STOSCs based on vacuum-deposited thin metal films exhibited power conversion efficiency exceeding 10%, solution-processed top transparent electrode (TE) is desirable for large-area and low-cost fabrication of STOSCs. Here, we present a self-assembled and knitted Ag nanoparticles/multi-walled carbon nanotubes composite thin film by solution process as transparent top electrode for STOSC. The composite film exhibits an extremely low sheet resistance of 14...