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Abstract: Road infrastructure significantly impacts the environment, and sustainability practices aim to minimize this impact. This includes reducing air and water pollution, preserving wildlife habitats, and reducing the consumption of natural resources. The goal is to minimize the impact of road development on the environment and natural resources while ensuring that the roads are safe, efficient, and meet the needs of communities. That is why there has been a growing trend toward using recycled materials in road construction in recent years. This is primarily driven by a desire to reduce road construction's environmental impact and conserve natural resources. Reclaimed asphalt pavement (RAP), made from recycled asphalt, can be used instead of traditional asphalt in road construction. RAP is created by milling or grinding up existing asphalt pavement that has been removed from roads, parking lots, or airport runways and is composed of asphalt binder and aggregate. Using RAP in pavement construction as a base course material helps to reduce the need for virgin aggregates and conserve natural resources. The use of RAP also offers several benefits, including reducing waste and reducing the environmental impact of road construction. But the quality of RAP can vary depending on its source and the process used to produce it for new pavement, making it essential to ensure proper quality control measures are in place. The base layer of a road is one of the layers of the road structure and plays a crucial role in the overall performance and longevity of the road. Asphalt emulsions are used in road construction and maintenance to provide a more effective, efficient, and sustainable alternative to traditional asphalt binders with the possibility of enhancing the properties of the base layer. Therefore, asphalt emulsions are workable at low temperatures, making them a good option for road construction in cold climates; they can be used in reconstruction and rehabilitation techniques such as cold in place recycling (CIR). Using cold in-place recycling process, asphalt emulsion stabilized mixture produced with RAP and asphaltenes, is waste material from Alberta oil sand with no significant value and useful application in the pavement industry. Asphaltenes is the most polar component since it has a higher molecular weight than the other components and adding asphaltenes to an asphalt mixture makes it stiffer. The objective of this research is to evaluate and compare the performance properties of the stabilized base course materials with different contents of RAP (50% RAP, 75% RAP and 100% RAP), asphalt emulsion with Asphaltenes. The impact of asphaltenes on the tensile strength and creep compliance performance of the recycled mixtures were investigated at the temperatures of - 20, -10, and 0oC and compared to the control mixture with no asphaltenes content. A mix design was performed to determine the optimum emulsion content (OEC), considering the optimum moisture content (OMC) needed for the compaction with the maximum density of the samples. For mixture modification, a different proportion of Asphaltenes (0.5% and 1%) was added to the mixture to determine physical and mechanical properties. To determine the permanent deformation, tensile strength, and low-temperature properties and cracking tolerance of the modified mixtures, indirect tensile strength (ITS), and creep compliance, strength tests, Hamburg wheel tracking test (HWT) and the indirect tensile asphalt cracking test (IDEAL CT) were performed on modified and unmodified mixtures. Results from the study indicate that modification of the mixtures with asphaltenes improved the performance of mixtures significantly compared to the control samples for mixtures with 50% RAP ,75% RAP and 100% RAP.The creep compliance analysis showed that modification of the mixture material with asphaltenes resulted in lower creep compliance values at below zero temperatures which consequently improves creep resistance in the modified mixtures for 50% RAP, 75% RAP . On the other hand, asphaltenes-modified samples had higher tensile strength and fracture energy than the control sample at room temperature. It shows that the samples are more resistant to cracking. However, only for the sample with 50% and 75% RAP, the IDEAL CT-Index analysis shows that adding asphaltenes will increase the potential for crack propagation of asphaltenes-modified mixtures regardless of the RAP content. According to the Hamburg wheel tracking test and RRI results, Asphaltenes modified mixture showed a significant improvement in the rutting resistance compared to the unmodified mixtures.