This paper is to investigate empirically the accuracy effects of photogrammetric point determination （PPD） using digital aerial stereo images with different level of JPEG compression as well as the suitability of adopting JPEG standard to compress digital aerial images. A pair of aerial black

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hite photos with 1∶8000 scale taken from a city proper was selected and scanned at a resolution of 25μm. We measured 18 image points with ISDM （Image Station Digital Mensuration） of Intergraph digital photogrammetric workstation and performed the bundle adjustment by single model with WuCAPS\-\{GPS\} （Wuhan GPS

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upported bundle block adjustment） developed by the authors. In processing various JPEG compressed images with Q

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actors from 1 to 100

the accuracy of the 3D coordinates of photogrammetric points was assessed and compared. The empirical results have shown that

when the compression ratios are under 10

the visual quality of JPEG compressed images is excellent and the accuracy of manual image mensuration is not influenced in essence. Although the significant differences of 3D coordinates of pass points are found in the bundle adjustment with different JPEG compressed images

the resulting accuracy of PPD will also meet the requirement for most photogrammetric applications. Therefore

a compression ratio of 10 could be recommended for photogrammetric point determination.