A two-wire transmitter comprising: a two-wire transmitter starter circuit for supplying power at the time of start-up, the two-wire transmitter starter circuit comprising a starter current generation circuit, wherein the starter current generation circuit comprises a first series circuit where a first resistor and a shunt regulator are connected in series, and a second series circuit where a switching element (M3, Q5) and a second resistor are connected in series; the shunt regulator comprises a current source connected to the first resistor in series, a control circuit configured to control a current value of the current source, and a first control terminal connected to a connection point of the switching element (M3, Q5) and the second resistor, and the first control terminal is an input terminal of the control circuit; the switching element (M3, Q5) comprises a second control terminal connected to a connection point of the first resistor and the shunt regulator; and the shunt regulator is configured to control the second control terminal to apply across the second resistor the same voltage as a reference voltage in the shunt regulator by increasing the current value of the current source if a voltage input from the first control terminal is higher than the reference voltage and decreasing the current value of the current source if the voltage input from the first control terminal is lower than the reference voltage; a current conversion unit configured to convert a detection signal of a sensor to a predetermined DC current; and two transmission lines (L1, L2) configuring a two-wire type transmission line, wherein the first series circuit, the second series circuit and the current conversion unit are connected in parallel to each other between the two transmission lines (L1, L2). a two-wire transmitter starter circuit for supplying power at the time of start-up, the two-wire transmitter starter circuit comprising a starter current generation circuit, wherein the starter current generation circuit comprises a first series circuit where a first resistor and a shunt regulator are connected in series, and a second series circuit where a switching element (M3, Q5) and a second resistor are connected in series; the shunt regulator comprises a current source connected to the first resistor in series, a control circuit configured to control a current value of the current source, and a first control terminal connected to a connection point of the switching element (M3, Q5) and the second resistor, and the first control terminal is an input terminal of the control circuit; the switching element (M3, Q5) comprises a second control terminal connected to a connection point of the first resistor and the shunt regulator; and the shunt regulator is configured to control the second control terminal to apply across the second resistor the same voltage as a reference voltage in the shunt regulator by increasing the current value of the current source if a voltage input from the first control terminal is higher than the reference voltage and decreasing the current value of the current source if the voltage input from the first control terminal is lower than the reference voltage; wherein the starter current generation circuit comprises a first series circuit where a first resistor and a shunt regulator are connected in series, and a second series circuit where a switching element (M3, Q5) and a second resistor are connected in series; the shunt regulator comprises a current source connected to the first resistor in series, a control circuit configured to control a current value of the current source, and a first control terminal connected to a connection point of the switching element (M3, Q5) and the second resistor, and the first control terminal is an input terminal of the control circuit; the switching element (M3, Q5) comprises a second control terminal connected to a connection point of the first resistor and the shunt regulator; and the shunt regulator is configured to control the second control terminal to apply across the second resistor the same voltage as a reference voltage in the shunt regulator by increasing the current value of the current source if a voltage input from the first control terminal is higher than the reference voltage and decreasing the current value of the current source if the voltage input from the first control terminal is lower than the reference voltage; a current conversion unit configured to convert a detection signal of a sensor to a predetermined DC current; and two transmission lines (L1, L2) configuring a two-wire type transmission line, wherein the first series circuit, the second series circuit and the current conversion unit are connected in parallel to each other between the two transmission lines (L1, L2).