The invention discloses a current transformer with an arc-shaped iron core and a coil and a manufacturing method thereof. The current transformer comprises an arc-shaped iron core, a secondary coil, an integral circuit module, a bracket and a porcelain insulator, wherein the secondary coil comprises a measurement winding and a power winding which are wound on the arc-shaped iron core, a power circuit and an integral circuit are arranged in the integral circuit module, the power winding and the power circuit are connected electrically, the measurement winding and the integral circuit are connected electrically, the arc-shaped iron core is arranged at the upper part inside the bracket, the integral circuit module is arranged at the bottom inside the bracket, the bracket is arranged in the porcelain insulator, and a through hole is formed at the bottom of the porcelain insulator. According to the current transformer disclosed by the invention, since the iron core is arc-shaped, when the current of a lead is measured, the lead needs neither to be mounted in a feed-through mode, nor to be fixedly mounted after being cut off, and therefore the lead can be mounted conveniently; in addition, the iron core and the coil are mounted in the porcelain insulator in a sealed way, and therefore the current transformer has excellent anti-fooling performance and can be used for a long time outdoors in a severe environment.