This study is expected to offer data guide and help halal slaughter enterprises in China. Taking rejected layer and Arbor Acre (AA) broiler as the object of the research, the effects of shackling times on meat quality in rejected layer and AA broiler chickens after slaughter were studied. The experimental samples were obtained by the process of halal slaughtering. The slaughter process does not have a syncope step. The shackling time is the time from shackled to slaughtered by the imam in this paper, while shackling time refers to the time from shackled to syncope in most other papers. Meat quality of rejected layer and AA broiler is expressed by these indicators, including deep body temperature changes, pH value (45 min after slaughter, known as pH1 value; 24 h after slaughter, known as pH2 value), color difference (L* value, a* value and b* value), water holding capacity (drip loss and cooking loss), T2b, T21 and T22 peak area by low field - nuclear magnetic resonance (LF-NMR), and inosine monophosphate (IMP) content. The effect of shackling time on meat quality of rejected layer and AA broiler chickens after slaughter was studied by the means of split plot experiment. Two chicken species (rejected layer, AA broiler) and 5 shackling time (0, 30, 60, 90 and 120 s) were included in this study. The results showed that when AA broiler was shackled for 90 s, these indicators, including deep body temperature changes, pH2 value, a* value, drip loss and cooking loss, all increased significantly, while T22 peak area and IMP content decreased significantly (P<0.05). Shackling time did not have significant influence on pH1 value, L* value, b* value, T2b peak area and T21 peak area for 90 s for AA broiler (P>0.05). When rejected layer was shackled for 120 s, pH2 value, a* value and cooking loss increased significantly, while IMP content decreased significantly (P<0.05). Shackling time did not have significant influences on deep body temperature changes, pH1 value, L* value, b* value, drip loss, T2b peak area, T21 peak area and T22 peak area for 120 s for rejected layer (P>0.05). GLM-multivariate analysis results showed that species had significant influences on deep body temperature changes, L* value, drip loss, cooking loss, T2b peak area, T21 peak area, T22 peak area and IMP content (P<0.05). Species did not have significant influences on pH1 value, pH2 value, a* value and b* value (P>0.05). Shackling time had significant effect on deep body temperature changes, a* value, drip loss, cooking loss, T22 peak area and IMP content (P<0.05). Shackling time did not have significant influence on pH1 value, pH2 value, L* value, b* value, T2b peak area and T21 peak area (P>0.05). Interactions between species and shackling time significantly affected a* value, drip loss, T22 peak area and IMP content (P<0.05), but did not have significant influence on deep body temperature changes, pH1 value, pH2 value, L* value, b* value, cooking loss, T2b peak area and T21 peak area (P>0.05). In conclusion, taking various factors into consideration, it will contribute to improving chicken quality after slaughter, and it is recommended that the optimum shackling time of AA broiler should range from 12 to 60 s, while that of rejected layer should range from 12 to 90 s. [ABSTRACT FROM AUTHOR]