The survey saw 400 Association of Teachers and Lecturers (ATL) respond and almost half (41%) knew pupils in their schools whose families have had to rely on food banks.
Dr Mary Bousted, general secretary of ATL, said: "The effect of hunger on pupils' learning is evident and it is shocking that in the 21st century so many pupils still come to school hungry with no means to buy lunch. With many families having to reply on charities such as food bank hand-outs, we risk returning to a Victorian era rife with inequality.
"It is encouraging that this year's Budget has committed to offer £10 million funding a year to expand breakfast clubs in up to 1,600 schools, starting from September 2017, to ensure more children have a nutritious breakfast as a healthy start to their school day. However, this is just a drop in the ocean for the thousands of pupils who miss out on breakfast and aren't entitled to FSM because they are from a low income working family.”
Overwhelmingly, members think that having lunch has a positive effect on pupils as 84% said it improves concentration, 91% said it improves pupils' learning, 88% said it has a positive effect on awareness, and 84% said it improves pupils' attainment.
Of the staff who are aware of a pupil coming to school hungry, and with no money to buy lunch, 15% bring in food for the pupil and 15% offer to buy them food themselves.
The survey also found that over half (52%) of education staff believe they have pupils in their school who should receive FSM but aren't entitled to them because they are from a low income working family, and are just above the income threshold for eligibility.
Although all children aged four to seven now qualify for FSMs regardless of income, if they are aged eight or over, and their parents receive working tax credits, children are automatically excluded from FSMs even if their family's income would otherwise made them eligible.
Bousted added: "ATL has long supported the universal provision of free school meals and at our conference this year members will debate the effect of poverty on learning and attainment."
"ATL also calls on the Government to support school holiday programmes that include meals and enrichment activities."