Abstract: In order to realize optical true time-delay(TDD) system of large-scale 2-D phased array antenna(PAA), a binary silicon-based integrated binary optical delay line technology based on silicon-based photonics was adopted. A 2-D PAA N×N TDD network was proposed. By using the symmetry of 2-D PAA structure and the independent control of row and column delays, the complexity of TDD networks can be reduced to (N-1)/2 (when N is odd) or N/2 (when N is even). Delay control scheme and the design of integrated delay chip were analyzed theoretically. Four kinds of silicon-based binary TDD chips were designed and implemented by taking 8×8 2-D phased array as an example. The delay of chips was measured. The beam scanning characteristics of 2-D phased array antenna were simulated and analyzed for the measured delay. The results show that TDD can satisfy the beam pointing requirement of PAA (angle error is less than 0.5°). The use of integrated optics technology greatly reduces the volume and the cost of the system. This study provides a feasible method for realizing TDD network of large-scale 2-D PAA.