1.58-bit FLUX is an advanced text-to-image generation model that employs 1.58-bit weights (values of {-1, 0, +1}) to quantify the FLUX.1-dev model while maintaining comparable performance for generating 1024x1024 images. This method does not require access to image data and relies entirely on the self-supervision of the FLUX.1-dev model. Additionally, a custom kernel has been developed to optimize 1.58-bit operations, achieving a 7.7x reduction in model storage, a 5.1x decrease in inference memory, and improved inference latency. Extensive evaluations in GenEval and T2I Compbench benchmarks show that 1.58-bit FLUX significantly enhances computational efficiency while maintaining generation quality.