A method for data transmission, comprising: receiving, by a terminal device, indication information, wherein the indication information is used for the terminal device to determine a first transmission power for uplink data within a target time unit; determining, by the terminal device, the first transmission power according to the indication information; and sending, by the terminal device, uplink data to a first network device at the first transmission power within the target time unit, wherein the indication information is determined through negotiation between the first network device and a second network device, and the first network device and the second network device are network devices to which the terminal device is connected through Long-Term Evolution, LTE- New Radio, NR, Dual Connection, DC, characterized in that, receiving, by the terminal device, indication information comprises: receiving, by the terminal device, from the first network device or the second network device, information of a time division multiplexing mode of the terminal device within the target time unit, the second network device being a network device sending downlink data to the terminal device; and wherein determining, by the terminal device, the first transmission power according to the indication information comprises: determining, by the terminal device, the first transmission power according to the information of the time division multiplexing mode, wherein when the target time unit is concurrently used for receiving downlink data and sending uplink data, the first transmission power is smaller than a maximum transmission power supported by the terminal device, and when the target time unit is merely used for sending uplink data, the first transmission power is the maximum transmission power supported by the terminal device. receiving, by a terminal device, indication information, wherein the indication information is used for the terminal device to determine a first transmission power for uplink data within a target time unit; determining, by the terminal device, the first transmission power according to the indication information; and sending, by the terminal device, uplink data to a first network device at the first transmission power within the target time unit, wherein the indication information is determined through negotiation between the first network device and a second network device, and the first network device and the second network device are network devices to which the terminal device is connected through Long-Term Evolution, LTE- New Radio, NR, Dual Connection, DC, characterized in that, receiving, by the terminal device, indication information comprises: receiving, by the terminal device, from the first network device or the second network device, information of a time division multiplexing mode of the terminal device within the target time unit, the second network device being a network device sending downlink data to the terminal device; and wherein determining, by the terminal device, the first transmission power according to the indication information comprises: determining, by the terminal device, the first transmission power according to the information of the time division multiplexing mode, wherein when the target time unit is concurrently used for receiving downlink data and sending uplink data, the first transmission power is smaller than a maximum transmission power supported by the terminal device, and when the target time unit is merely used for sending uplink data, the first transmission power is the maximum transmission power supported by the terminal device. receiving, by the terminal device, from the first network device or the second network device, information of a time division multiplexing mode of the terminal device within the target time unit, the second network device being a network device sending downlink data to the terminal device; and wherein determining, by the terminal device, the first transmission power according to the indication information comprises: determining, by the terminal device, the first transmission power according to the information of the time division multiplexing mode, wherein when the target time unit is concurrently used for receiving downlink data and sending uplink data, the first transmission power is smaller than a maximum transmission power supported by the terminal device, and when the target time unit is merely used for sending uplink data, the first transmission power is the maximum transmission power supported by the terminal device. determining, by the terminal device, the first transmission power according to the information of the time division multiplexing mode, wherein when the target time unit is concurrently used for receiving downlink data and sending uplink data, the first transmission power is smaller than a maximum transmission power supported by the terminal device, and when the target time unit is merely used for sending uplink data, the first transmission power is the maximum transmission power supported by the terminal device.