Objective: The aim of this study was to find a better technique for the cell block preparation. Study Design: We developed a novel capsule-based technique and applied it to different cell block preparation materials including plasma thromboplastin (PT) clot and agarose gel-embedding medium, in order to concentrate the cells in a limited field, then compared the result with the widely used, modified alcohol fixative preparation technique based on specimen adequacy and diagnostic accuracy. Twenty-eight nongynecologic body fluids and 41 gynecologic Liqui-PREP™ (LGM International Inc., Fort Lauderdale, Fla., USA) cytology specimens were collected for cell block preparation. We performed routine hematoxylin and eosin staining on the cell block sections, which were scored according to four specimen adequacy parameters: background, cellularity, nuclear preservation and cytoplasmic preservation. The differences between the diagnostic results of cell block slide and conventional cytology smear were also presented. Results: The capsule-based PT clot technique in nongynecologic body fluids provided more cellularity in the cell block sections and reduced atypical diagnosis when compared to conventional smears. Conclusion: We suggest the capsule-based PT clot technique is a better technique for nongynecologic body fluids in the preparation of a satisfactory cell block.