Smoke screen has the characteristics of high cost-effectiveness ratio and convenient deployment in the application of countering precision-guided weapons. In view of the lack of quantitative evaluation methods for smoke screen jamming effectiveness at present, a smoke screen jamming effectiveness assessment method based on image correlation and image structure similarity is proposed according to the guidance mechanism of infrared guidance system. To improve the applicability of the tracking error-interference success rate evaluation criterion, an effective masking probability index for the smoke screen is put forward. The interference processes of smoke screen are analyzed through the external field experiment, and the test data are quantitatively analyzed using the mean normalized cross correlation (C₂) and structural similarity index (SSIM). And the quantitative evaluation criterion for effectiveness smoke interference is proposed on the basis of the evaluation results. The experimental results show that the smoke-screen jamming effect can be quantitatively evaluated based on image quality evaluation and effective obscuring probability. When the value of C₂ drops to less than 0.4 or the value of SSIM value is less than 0.72, the infrared guidance system loses the target and the smoke-screen jamming is effective. For smoke bombs loaded with nano-smoke materials and those enriched with carbon black aggregates, the probability of effective smoke screen masking is 0.503 and 0.659, respectively.