Jainca County, Chentsa County or Jainzha County (Tibetan: གཅན་ཚ།, Wylie: gcan tsha; Chinese: 尖扎县; pinyin: Jiānzhā Xiàn) is a county in Huangnan Tibetan Autonomous Prefecture in Qinghai Province, China, to Tibetans in the area known as Malho Prefecture, part of Amdo.

There are six townships, three towns and a total of 79 administrative villages in Chentsa county.

The county has an area of 1714 square kilometres and a population of ~50,000 (2001), 67% Tibetan.

The county seat is the town of Markhu Thang.

Jainca County is made up of 3 towns and 6 townships: Jainca County has a cold semi-arid climate (Köppen BSk) and it set the record high temperature of Qinghai[citation needed], at 40.3 °C (104.5 °F), on July 24, 2000.