Introduction: - About 300, 000 women died during and following pregnancy and childbirth in 2017. Even if, maternal mortality ratio dropped by about 38% worldwide between 2000 and 2017, maternal mortality is still unacceptably high including Ethiopia, where ratio was reported 412per100,000 live births in 2015.The time between the onset of an obstetric emergency and definitive care is critical for the survival of the mother and her baby. There is scarce the study which indicate the delay level and what factors contribute for delay in receiving care once the pregnant mothers reach the health facility in the study area. Objective: -To assess the third delay and associated factors among laboring mothers attending Public Health Facilities in Gurage Zone, Southern Ethiopia, 2020. Method and materials: -Facility based cross-sectional study was conducted public health facilities in Gurage zone from January01/2020 to March30/2020. A multistage stratified sampling technique was used to collect data from 558 mothers in labor and using structured and pre-tested questionnaire. For health facility data observational checklist was considered. The study subjects were selected by systematic sampling technique. Data entry and analysis was made by using Epi Data version 3.1 and SPSS version 20.0 respectively. Both bivariate and multi variable analysis were carried out to identify association between dependent and independent variables. Variable having P.value <0.25 in bivariate analysis was candidate for multivariable analysis. Variables with P< 0.05 were considered as statistically significant. Result: -The response rate was 97.3% and mean age of the study participants was 28.36(±5.488). Magnitude of third delay was 169 (31.1%). Non formal education[AOR= 1.6; 95% CI: 1.0, 2.5], unemployed mothers [AOR= 2.0; 95% CI: 1.2, 3.2], refusal of medical procedure [AOR= 2.2; 95% CI: 1.1, 4.3], absence of skilled delivery care provider [AOR= 5.6;95% CI: 3.2, 9.8], instrumental delivery [AOR= 2.7; 95 % CI: 1.5, 4.8] were significantly associated with third delay Conclusion: -There is high magnitude of third delay in the study area. Educational status of mothers, occupation of mothers, absence of skilled delivery care provider, mode of delivery and refusal of medical procedure were significant association with third delay. Therefore, educating mothers, creating income generation mechanism work and sufficient avail skilled health professionals are important to reduce third delay.