The Western Satraps, Western Kshatrapas, or Kshaharatas (35–405) are Saka rulers of the western and central part of India (Saurashtra and Malwa: modern Gujarat, Southern Sindh, Maharashtra, Rajasthan and Madhya Pradesh states).

Their state, or at least part of it, is called "Ariaca" according to the Periplus of the Erythraean Sea.They are successors to the Indo-Scythians, and are contemporaneous with the Kushans who rule the northern part of the Indian subcontinent and are possibly their overlords, and the Satavahana (Andhra) who rules in Central India.

They are called "Western" in contrast to the "Northern" Indo-Scythian satraps who rule in the area of Mathura, such as Rajuvula, and his successors under the Kushans, the "Great Satrap" Kharapallana and the "Satrap" Vanaspara.

Although they call themselves "Satraps" on their coins, leading to their modern designation of "Western Satraps", Ptolemy in his 2nd century "Geographia" still called them "Indo-Scythians".

Altogether, there are 27 independent Western Satrap rulers during a period of about 350 years.

The word Kshatrapa stands for satrap, and its equivalent in Persian Ksatrapavan, which means viceroy or governor of a province.