网络科学是从交叉学科研究成长起来的一个新兴的学术领域。致力于研究复杂网络的性质，并且应用这些性质去研究一些具有网络特点的领域，比如信息技术网络，计算机网络，生物圈网络，学习和认知网络，社会关系网络以及经济和金融网络。这个领域以数学中的图论为理论基础，从物理中的统计力学，计算机科学中的数据挖掘和信息可视化，统计学中的推断建模，以及社会学和经济学中的社会结构理论等学科和分之中汲取方法论营养。美国国家科研委员会（National Research Council）将网络科学定义为 “研究物理，生物，和社会现象的网络化表达，创建针对这些象限具有预测效果的模型” 的学科。

In computer and network science, network theory is the study of graphs as a representation of either symmetric relations or, more generally, of asymmetric relations between discrete objects. Network theory is a part of graph theory.

It has applications in many disciplines including statistical physics, particle physics, computer science, electrical engineering, biology, economics, operations research, climatology and sociology. Applications of network theory include logistical networks, the World Wide Web, Internet, gene regulatory networks, metabolic networks, social networks, epistemological networks, etc.; see List of network theory topics for more examples.