This thesis consists of three studies on international macroeconomics and finance. In the first study, I examine the relationship between contract enforcement and FinTech lending. After controlling for firm characteristics, I find a negative relationship between contract enforcement and FinTech lending in China. This relationship significantly differs from the bank lending that is positively correlated with contract enforcement. The difference is due to FinTech’s information advantages from using machine learning algorithms with big data rather than relying on loan officers for credit approval and post-loan monitoring. The negative relationship between contract enforcement and FinTech lending is stronger for firms with more financial constraints. In the second study, I explore the economic effect of the West Development Policy in China. The findings show that the program promotes economic development. Furthermore, it leads to an increase in the industry sector’s share of GDP and a decline in the agriculture’s sector share that transforms the economy. Microeconomic evidence indicates that low capital-intensive and politically connected firms invest more because of the program. In the third study, I attempt to answer the question of why the distance effect is persistently negative in the gravity model after the development of information technologies over the last few decades. I provide a new perspective on this effect on international asset investment by considering investment concentration and relative geographical locations.