Despite the efforts of airlines to differentiate and position their organizations for successful operations in the competitive aviation business, however, mantaining customers’ loyalty appears to be a growing concern and challenge to managers in the sector in Nigeria. This study therefore assessed the effect of airlines marketing attributes on customers’ loyalty at the Port Harcourt International Airport, Rivers State.This study adopted the cross-sectional survey research design whereby primary data were obtained from 246 passengers of functional airlines at Port Harcourt International Airport through the questionnaire method. The data were analysed using simple percentage, mean score, standard deviation and multiple regression aided by statistical package for social sciences (SPSS). The findings revealed that airlines’ marketing attributes dimensions( affordability, staff friendliness and online booking) were not well perceived by passengers and therefore not significant enough earn passengers’ loyalty. Based on the findings of the study, it was concluded that all the dimensions of airline marketing attributes did not have a significant effect on customers’ loyalty. The study recommended reduction in air fare, improvement in air travel processes at the airport and better customer relationship management strategies for customers’ retention.