More than 90 pupils in years 1-4 were suspended in 2017/18, 20 more than in the previous school year.
The information comes from recently published Department of Education (DE) statistics for the number of suspensions and expulsions.
In total, 4,069 schoolchildren were suspended across all age groups. That figure includes 583 children who were suspended three or more times.
The number of pupils expelled fell to 15, down from 33 in 2016/17.
The total number of suspensions issued by schools in the 2017/18 school year was 6,491.
Attacks on staff
Figures also highlight 110 occasions when students were suspended for substance abuse and 263 times when staff were physically attacked.
They show 1,535 instances of pupils being suspended for a physical attack on another pupil.
More boys were suspended than girls.
Two thirds of those expelled were from years eight to 10.
The most common reason for expulsion was "persistent infringements of relatively minor school rules".
There are currently more than 300,000 pupils in Northern Ireland primary and post-primary schools.
The statistics are supplied to DE by the Education Authority.