Tokomaru is a small town in the district of Horowhenua, in the southwestern North Island of New Zealand. It is located 18 kilometres southwest of Palmerston North, and a similar distance northeast of Shannon. The Tokomaru railway station on the North Island Main Trunk was open from 1885 to 1982.

The Tokomaru Steam Engine Museum features a collection of antique steam engine machinery, much of which is still operational. The collection includes a 1904 Fowler traction engine, an 1897 Aveling & Porter portable engine and a huge 335 hp Filer & Stowell stationary engine-compressor ex the Imlay Freezing Works, Wanganui. The museum is open by appointment.

Tokomaru has two public reserves, the Tokomaru Domain, which includes a sports field and hall, and Horseshoe Bend reserve.

The town has a locally run combined store and post office.

There are two factories on the outskirts of Tokomaru. One of them, Stevensons Structural Engineers, built structural steel buildings, and employed many of the Tokomaru residents until it went into liquidation on Friday 3rd March 2023. The other is a former dairy factory that was being renovated in 2011.

Tokomaru is defined by Statistics New Zealand as a rural settlement and covers 2.91 km (1.12 sq mi). It had an estimated population of 640 as of June 2024, with a population density of 220 people per km. It is part of the larger Miranui statistical area.

Historical population for Tokomaru

Year	Pop.	±% p.a.
2006	459	—
2013	483	+0.73%
2018	531	+1.91%
Source:

Before the 2023 census, the settlement had a smaller boundary, covering 2.54 km (0.98 sq mi). Using that boundary, Tokomaru had a population of 531 at the 2018 New Zealand census, an increase of 48 people (9.9%) since the 2013 census, and an increase of 72 people (15.7%) since the 2006 census. There were 192 households, comprising 264 males and 267 females, giving a sex ratio of 0.99 males per female, with 147 people (27.7%) aged under 15 years, 87 (16.4%) aged 15 to 29, 237 (44.6%) aged 30 to 64, and 60 (11.3%) aged 65 or older.

Ethnicities were 84.7% European/Pākehā, 27.1% Māori, 4.0% Pasifika, 3.4% Asian, and 3.4% other ethnicities. People may identify with more than one ethnicity.

Although some people chose not to answer the census's question about religious affiliation, 58.8% had no religion, 28.8% were Christian, 0.6% were Hindu, 0.6% were Buddhist and 2.3% had other religions.

Of those at least 15 years old, 63 (16.4%) people had a bachelor's or higher degree, and 72 (18.8%) people had no formal qualifications. 48 people (12.5%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 222 (57.8%) people were employed full-time, 39 (10.2%) were part-time, and 6 (1.6%) were unemployed.

Miranui statistical area, which surrounds but does not include Shannon, and includes Mangaore, covers 296.88 km (114.63 sq mi) and had an estimated population of 2,030 as of June 2024, with a population density of 6.8 people per km.

Historical population for Miranui

Year	Pop.	±% p.a.
2006	1,533	—
2013	1,587	+0.50%
2018	1,788	+2.41%
Source:

Miranui had a population of 1,788 at the 2018 New Zealand census, an increase of 201 people (12.7%) since the 2013 census, and an increase of 255 people (16.6%) since the 2006 census. There were 633 households, comprising 909 males and 882 females, giving a sex ratio of 1.03 males per female. The median age was 34.6 years (compared with 37.4 years nationally), with 474 people (26.5%) aged under 15 years, 303 (16.9%) aged 15 to 29, 828 (46.3%) aged 30 to 64, and 189 (10.6%) aged 65 or older.

Ethnicities were 88.1% European/Pākehā, 19.3% Māori, 3.4% Pasifika, 3.9% Asian, and 2.5% other ethnicities. People may identify with more than one ethnicity.

The percentage of people born overseas was 10.2, compared with 27.1% nationally.

Although some people chose not to answer the census's question about religious affiliation, 58.2% had no religion, 32.2% were Christian, 1.0% had Māori religious beliefs, 0.3% were Hindu, 0.2% were Buddhist and 1.3% had other religions.

Of those at least 15 years old, 213 (16.2%) people had a bachelor's or higher degree, and 276 (21.0%) people had no formal qualifications. The median income was $36,700, compared with $31,800 nationally. 198 people (15.1%) earned over $70,000 compared to 17.2% nationally. The employment status of those at least 15 was that 759 (57.8%) people were employed full-time, 180 (13.7%) were part-time, and 42 (3.2%) were unemployed.

Tokomaru School is a co-educational state primary school for Year 1 to 8 students, with a roll of 81 as of August 2024.