64.69% of the Population of Mamuju Tengah Regency in 2023 was aged 15-59 years.

The majority of the population in this region, or approximately 64.69%, are of productive age, namely between 15-59 years old, totaling 91,352. According to a 2023 publication by the Central Statistics Agency (BPS), the number reached 91,352. The remaining population consists of those aged 0-14 years (children) at approximately 28.73%, and 6.59% are the elderly population aged over 60 years.

The population of Mamuju Tengah Regency was recorded at 141,220 as of 2023. Over the past nine years, the population has continuously increased. Over the last five years, the Compound Annual Growth Rate (CAGR) has been 1.54%.

Compared to other districts/cities in West Sulawesi province, Mamuju Tengah Regency ranks sixth in terms of population. Nationally (by island), it ranks 59th.

The following is the population by age group in Mamuju Tengah Regency as of December 2023, sourced from a publication by the Central Statistics Agency (BPS):

* Age 0-4 years: 13,100 (9.28%)
* Age 5-9 years: 14,030 (9.93%)
* Age 10-14 years: 13,440 (9.52%)
* Age 15-19 years: 13,450 (9.52%)

* Age 20-24 years: 13,730 (9.72%)
* Age 25-29 years: 11,860 (8.4%)
* Age 30-34 years: 11,120 (7.87%)
* Age 35-39 years: 10,200 (7.23%)
* Age 40-44 years: 9,570 (6.78%)
* Age 45-49 years: 8,310 (5.88%)
* Age 50-54 years: 7,750 (5.49%)
* Age 55-59 years: 5,360 (3.8%)
* Age 60-64 years: 3,730 (2.64%)
* Age 65-69 years: 2,360 (1.67%)
* Age 70-74 years: 1,520 (1.08%)
* Age 75 years and over: 1,690 (1.19%)