The Panther (Sd.Kfz.171) was originally known as Pz.Kpfw.V, but was renamed Pz.Kpfw.Panther in February, 1944. Panther was a response to the Soviet T-34, which was difficult to handle with the earlier Pz.Kpfw.III and Pz.Kpfw.IV. At least 23 Ausf.D Panthers were fitted with a clutch-brake steering system instead of the single-radius system, although the single-radius system was retrofitted to most of these. The first 251 Panthers were powered by the 650hp Maybach HL210P30 engine; the newer HL230P30 was essentially a bored-out HL210P30. The radio operator was provided with a slot in the front plate for observation and firing his machine gun, and the driver had a vision port in the glacis plate. The commander's cupola was cylindrical, and had six vision slits around the circumference. Initially, the Kw.K.42 was capped by a round single-baffle muzzle brake, but this was replaced with a double-baffle version. Schuerzen side skirts were mounted starting in April 1943, and the three-barrel smoke dischargers were no longer mounted on the turret sides after June 1943 since small arms fire could set them off. The road wheels were reinforced during the production run, with rivets being added between each rim bolt. New 24-bolt road wheels were introduced in August 1943. The left turret communication port was also deleted during production. The Panther was rushed into production, and the lack of an adequate test program resulted in unreliable components, including the engine, transmission, and final drives. The final drives were never adequately strengthened.

Ausfuehrung A (Sd.Kfz.171) intoduced a new turret. This turret included a new commander's cupola with periscopes and a mount for an anti-aircraft machine gun. A periscope was provided for the loader, and the turret weld joints were 90° angles instead of the dovetailed joints on Ausf.D. A new turret traverse mechanism was installed, which allowed different traverse speeds depending on the engine speed. A ball mount for the hull machine gun and a monocular telescopic sight for the gunner were introduced in November 1943. Also in November, an engine governor set at 2500rpm was installed. With the engine governor, turret traverse speed was limited to one revolution in 18 seconds. Later production Ausf.A turrets had the side pistol ports deleted.

The exhaust pipes were modified after the addition of a crew heater which drew air in from the outside; this left the left exhaust manifold without a cooling airflow. Two more pipes were then installed on either side of the left exhaust pipe, which provided a route for cooling air through the left side of the engine compartment.