The present invention provides a fully automatic fecal occult blood detecting analyzer, which is used to detect a sample box (30). The sample box (30) includes a transparent sleeve and a feces collector and test strips provided in the transparent sleeve. The fully automatic fecal occult blood detecting analyzer includes a feeding chain (10) and a main conveying chain (20) a plurality of clamping devices (40) for clamping the sample box (30) are provided on the feeding chain (10) and the main conveying chain (20), respectively a transferring device is configured to transfer the sample box (30) from the feeding chain (10) to the main conveying chain (20) a pressing device (90) and an image acquisition device is configured to acquire colored tape information presented on the test strips in the sample box (30) on the main conveying chain (20). The present invention can implement continuous detection and accurate location of a plurality of sample boxes (30) without turning over and tilting the sample boxes (30). Besides, the sample boxes (30) can be pressed accurately so that diluents of fecal samples react with test strips to complete detection.