A method for power control, comprising: receiving, by a terminal, first configuration information sent by a network device, wherein the first configuration information is used for determining power of an uplink data channel of a first message, the first message comprises a preamble and the uplink data channel; characterized in that the first configuration information comprises at least one power adjustment parameter, the at least one power adjustment parameter is used for determining a ratio between the power of the uplink data channel and power of the preamble and comprises a first power parameter and a second power parameter, the first power parameter is used for representing the ratio between the power of the uplink data channel and the power of the preamble, and the second power parameter is used for representing a power ramping value of the uplink data channel; and determining, by the terminal, the power of the uplink data channel based on the power of the preamble and the ratio between the power of the uplink data channel and the power of the preamble, comprising: determining, by the terminal, an expected received power of the uplink data channel by using the following formula: P O _ NOMINAL _ PUSCH, ƒ, c = P O _ PRE + Δ PREAMBLE _ PUSCH + Δ Boost _ PUSCH, wherein P O _ NOMINAL _ PUSCH, f,c represents the expected received power of the uplink data channel, a subscript f represents a carrier, and a subscript c represents a cell, P O_PRE represents an expected received power of the preamble, Δ PREAMBLE_PUSCH represents the first power parameter, and Δ Boost _ PUSCH represents the second power parameter; and determining, by the terminal, the power of the uplink data channel based on the expected received power of the uplink data channel by using the following formula: P PUSCH = min P CMAX, ƒ, c, P O _ NOMINAL _ PUSCH, ƒ, c + PL ƒ, c, wherein P PUSCH represents the power of the uplink data channel, P CMAX,f, c represents a maximum transmit power of the first message allowed by the terminal, and PL f,c represents a path loss measured by the terminal by using a cell reference signal. receiving, by a terminal, first configuration information sent by a network device, wherein the first configuration information is used for determining power of an uplink data channel of a first message, the first message comprises a preamble and the uplink data channel; characterized in that the first configuration information comprises at least one power adjustment parameter, the at least one power adjustment parameter is used for determining a ratio between the power of the uplink data channel and power of the preamble and comprises a first power parameter and a second power parameter, the first power parameter is used for representing the ratio between the power of the uplink data channel and the power of the preamble, and the second power parameter is used for representing a power ramping value of the uplink data channel; and determining, by the terminal, the power of the uplink data channel based on the power of the preamble and the ratio between the power of the uplink data channel and the power of the preamble, comprising: determining, by the terminal, an expected received power of the uplink data channel by using the following formula: P O _ NOMINAL _ PUSCH, ƒ, c = P O _ PRE + Δ PREAMBLE _ PUSCH + Δ Boost _ PUSCH, wherein P O _ NOMINAL _ PUSCH, f,c represents the expected received power of the uplink data channel, a subscript f represents a carrier, and a subscript c represents a cell, P O_PRE represents an expected received power of the preamble, Δ PREAMBLE_PUSCH represents the first power parameter, and Δ Boost _ PUSCH represents the second power parameter; and determining, by the terminal, the power of the uplink data channel based on the expected received power of the uplink data channel by using the following formula: P PUSCH = min P CMAX, ƒ, c, P O _ NOMINAL _ PUSCH, ƒ, c + PL ƒ, c, wherein P PUSCH represents the power of the uplink data channel, P CMAX,f, c represents a maximum transmit power of the first message allowed by the terminal, and PL f,c represents a path loss measured by the terminal by using a cell reference signal. determining, by the terminal, an expected received power of the uplink data channel by using the following formula: P O _ NOMINAL _ PUSCH, ƒ, c = P O _ PRE + Δ PREAMBLE _ PUSCH + Δ Boost _ PUSCH, wherein P O _ NOMINAL _ PUSCH, f,c represents the expected received power of the uplink data channel, a subscript f represents a carrier, and a subscript c represents a cell, P O_PRE represents an expected received power of the preamble, Δ PREAMBLE_PUSCH represents the first power parameter, and Δ Boost _ PUSCH represents the second power parameter; and determining, by the terminal, the power of the uplink data channel based on the expected received power of the uplink data channel by using the following formula: P PUSCH = min P CMAX, ƒ, c, P O _ NOMINAL _ PUSCH, ƒ, c + PL ƒ, c, wherein P PUSCH represents the power of the uplink data channel, P CMAX,f, c represents a maximum transmit power of the first message allowed by the terminal, and PL f,c represents a path loss measured by the terminal by using a cell reference signal.