It is a fact that thoughts interact from time to time in their historical course and as a result, similarities and differences occur. In this study, Plotinus, the founder of Neoplatonism, and the early period Gnostic Christian movements, which are semi-religious and semi-philosophical thought movements, are subject to a comparative analysis of the God teachings of Basilidenianism, Valentinianism and Marcionism. In this context, we explained Neoplatonism and both the beliefs and thoughts of these movements and tried to identify the similarities and differences between them. Because we think that there are common features between the teachings of Plotinus and the Gnostic thought in terms of God, Divine beings, dualist thought and understanding of the world. However, there are some differences in matters such as the material realm, the Demiurge, the emergence of the realm, its value, rise and fall. Plotinus wrote the Enneads, meaning nines in Greek. II. In Ennead's ninth book, he included the Gnostics and criticized their metaphysics and epistemology. Although Plotinus criticizes the Gnostics, there are some important similarities with them. In this context, we believe that some of the claims made by Plotinus towards the early Gnostics are correct and appropriate. We witness that the Gnostics used it to ground and interpret the Platonic thought-provoking Christian faith. In doing so, we can say that they distorted the concepts in Plato's thought and moreover, they gave them a mystical form. Therefore, it is possible to say that there are Platonic philosophical concepts in the philosophical background of today's Christian theology, which are relatively distorted or, in the most optimistic way, decontextualized. In particular, problems such as God, the supernatural realm, divine beings, God-nature relationship have a decisive feature in this discussion. It is possible to deal with issues such as pantheism and panentheism, which are frequently discussed in Western thought, in this context and to argue their philosophical and theological roots in the discussions between these groups. The dimensions and depth of this interaction are the subject of a separate study. With this study, we aim to trace the effects of Neoplatonism on subsequent religions and philosophies, and to determine how the understanding of God, which is an important subject of religion and philosophy, was interpreted in two traditions that emerged in the second century. With this research, the doctrine of Supreme Being, One and Emanation, which is accepted as the main vein of Neo-Platonism, is one of the most important intellectual codes for both Plotinus and the early Gnostic groups, both systems bring similar interpretations to dualism in metaphysical matters and are influenced by each other, but in the world of matter, they are quite different from each other. It was concluded that they were separated. In this research, we tried to apply especially to the first type of sources. Due to, Plato's own works and Plotinus's Enneads have been an important source of reference for us. We also used qualified secondary sources on Plato and Plotinus. However, since there are not enough original and authentic sources about other Gnostic groups, we have applied to recent sources as much as possible. Recently, Gnostic thought has attracted a lot of attention in academic circles. In this research, we also tried to include academic studies on Gnostics. This research is a source for some of the discussions we have mentioned above. To what extent the Gnostics understood the Platonic philosophy correctly and to what extent they remained faithful to the authentic meanings of the Platonic concepts is another subject of study. The same is true for Plotinus. From this point of view, the extent to which Islamic Peripatetic and Israki philosophers, who were influenced by Plato and Neo Platonism, took part in this interaction and put forward original ideas, is an issue that researchers of Islamic philosophy should focus on.