Abnormal uterine bleeding is a serious problem among women of late reproductive age. Cervical cancer is one of the reasons of AUB and Pap smear is the best way to diagnose it. Blood has negative effects on Pap smear especially in AUB with great blood. One of the effective solutions for lysing RBC is Carnoy’s. This study aims to compare two methods of fixation in bloody Pap smear by Carnoy’s and normal spray in samples from women with AUB. This study was done on 204 bloody Pap smear from 102 women with AUB that referred to Zeinabieh and Faghihi hospitals of Shiraz University of Medical Sciences from2012-2013. After observing uterine bleeding in each subject, two samples were provided using usual Pap smear method; one of the slides was fixed by normal spray and the other slide fixed by Carnoy’s solution for20 minutes. After staining (Papanicolaou method), two pathologists performed a double-blind trial to analyze them. Data analysis was done using SPSS. 82 samples did not have cell adequacy. Squamous cells in Carnoy’s-fixed slides were more than spray-fixed ones (p=0.024). The decrease in the number of RBC on slides and the increase in the clarity of slides in Carnoy’s-fixed samples were more than sprayfixed slides (p=0.001), while identifying inflammatory cells(p=0.832) and microbial factors (p=1) in both methods showed no significant difference. Carnoy’s solution can be used as an effective fixative in bloody Pap smear from women with abnormal uterine bleeding.