Angiogenesis research has become one of the most important areas in biomedical research. At the time of writing this review, there were approximately 3536 articles published in the year of 2008 alone on the topic of angiogenesis. The fast expansion of this research field demands development of rigorous, reliable, stable, convenient, and clinically relevant assay systems for disease diagnosis, prognosis, therapeutic evaluation, drug discovery, and mechanistic studies at the molecular level. Here, we discuss several commonly used in vivo angiogenesis models by systematically analyzing and pointing out pitfalls of each assay. Owing to existence of numerous assays and the limitation of text, it is impossible to discuss all these assays in this article. Here we select several most commonly used angiogenesis assays performed in various species including mice, chicks and zebrafish for further in-depth discussion. We hope this information will be valuable for improving current angiogenesis research.