A method, a device, and a computer program product for parallel data transmission are provided in embodiments of the present disclosure. The method includes obtaining attributes of data to be transmitted from a first storage device to a second storage device and a network condition between the first storage device and the second storage device. The method also includes determining a number of concurrencies and a data slice size for use in parallel transmission of the data based on the attributes of the data and the network condition, and transmitting the data in parallel between the first storage device and the second storage device using the determined number of concurrencies and the data slice size. In embodiments of the present disclosure, during parallel data transmission, the appropriate number of concurrencies and data slice size can be selected according to attributes of data to be transmitted and an actual network condition.