Arms trade is an important expenditure in military spending． There is a very complex relationship between military spending and economic growth． The paper introduces the arms trade under the framework of military expenditure and economic growth． Using the Solow economic growth model and selecting the two-way fixed effect estimator，panel regression analysis is carried out on the data of 25 countries to study the relationship between arms trade，military spending and economic growth． The study finds that when military spending and net arms exports are the only factors for economic growth，it will result in a negative impact on economic growth，but if the country is a net exporter of weapons，the negative impact of high military spending on economic growth will be weakened．