This article explores the determinants that affect the transportation outsourcing strategy of the express delivery company in Taiwan. The results show that the following situations result in higher outsourcing probability: customer companies belonging to the high-tech industry, customers bringing higher freight revenue, customers having a better relationship with the case study company, and customersâ[euro](TM) company having a bigger scale. The findings provide enterprises with a reference of decision making to follow in implementing the transportation outsourcing measure for different customersâ[euro](TM) needs. The outsourcing strategy increases the flexibility of operating funds to enhance customer service quality.