Insects are not only the most species—rich group on Earth, they also play numerous crucial roles in ecosystem functioning and the global economy. The conservation of insect diversity is therefore a topic of global importance. However, insects are mostly ignored by “biodiversity” research; for example, relationships between insect diversity and vegetation or climate change remain widely unknown. This paper makes suggestions for further research into insect diversity patterns based on two typical forest types in northern China: Changbai Mountain, northeast China and Dongling Mountain, central northern China. Plants and climate have been well studied in these areas but substantial knowledge gaps prevail in relation to insect diversity patterns. It is therefore important to investigate insect biodiversity patterns in these regions.