Organic semiconductors might enable new applications in low-cost, light-weight, flexible electronics. To build a solid foundation for these technologies, more fundamental studies of electro-mechanical properties of various types of organic semiconductors are necessary. Here we perform basic studies of charge transport in highly crystalline solution-processed organic semiconductors as a function of applied mechanical strain. As a test bed, we use small molecules crystallized on thin plastic sheets, resulting in high-performance flexible field-effect transistors. These devices can be bent multiple times without degradation to a radius as small as ~200 μm, demonstrating that crystalline solution-processed organic semiconductors are intrinsically highly flexible. This study of electro-mechanical properties suggests that solution-processable organic semiconductors are suitable for applications in flexible electronics, provided that integration with other important technological advances, such as device scalability and low-voltage operation, is achieved in the future.