Province Wellesley (or Seberang Perai in Malay), is a narrow hinterland opposite Penang island on the Malay Peninsula, which together with the island forms the Malaysian state of Penang. It was ceded to the British East India Company by the Sultan of Kedah in 1790, and been part of the settlement and state of Penang ever since. The chief town is Butterworth, and it is connected to Penang island by a bridge and by ferry services. There is a Malayan Railway station and a container terminal at Butterworth.

The province is probably named after Richard Wellesley, 1st Marquess Wellesley, Governor of Madras and Governor-General of Bengal (1797-1805) or his brother Arthur Wellesley, 1st Duke of Wellington.