The Parenting Network, based in the Guildhall, gathered more than 500 boxes of essential supplies in a single day following a desperate rallying call.
So far, more than £3,000 in funding has been raised, and all donated supplies are planned to be sent to the Polish-Ukrainian border on Saturday
Matt Foster, chief executive of the charity, will be leading the contingent of three people to eastern Europe, making sure the aid reaches those who need it.
Shelly Crocker, chief operating officer for The Parenting Network, said she was overwhelmed with the support so far.
She told The News: ‘It’s astronomical.
‘We’re so grateful to the kindness of the local community.
‘How much everyone wants to help is tangible here right now.
‘We’re opening parcel after parcel after parcel.
‘A lot of love has gone into these gifts, and clearly money as well.
‘Even small things have been packaged and sent with clear compassion, and we’re really grateful.’
Ms Crocker added most of the boxes contain supplies suitable for families with children and small babies.
Packages include blankets, nappies, baby wipes, toiletries, baby comforters, sanitary items and other essentials.
People can support the scheme by purchasing items from the charity’s Amazon wish list.
All financial donations will go to buying more aid items when the team is on the Polish-Ukrainian border, or to fuel the lorries transporting the parcels.
The expedition will meet up with their colleagues from Bridge to Unity, who provided humanitarian aid in Afghanistan in the past.
Ms Crocker said her colleagues at the Guildhall have processed an ‘astronomical’ amount of packages, and was not surprised by the heart-warming support from Portsmouth residents.
She added: ‘We just deeply wanted to help in some way, and we are so well resourced with the baby bank that we probably thought we could do something.
‘Portsmouth is a remarkable city, and we should never underestimate our ability to show love, kindness and compassion to those who need it most.
‘From our experiences, we’ve never doubted the kindness that the local community show when someone is in need.’
Portsmouth South MP Stephen Morgan is planning to visit The Parenting Network this Thursday to package donations, and praised the efforts so far.
He said: ‘The generosity of our city always shines through in times of crises.
‘I'm so pleased that our city's own Parenting Network are partnering with Bridge to Unity UK to deliver clothes and other essential supplies to the people of Ukraine.
‘Their inspirational efforts give us hope that we can all contribute to the humanitarian effort that is now desperately needed.
‘I've been promoting opportunities for local people to give what they can and hope to roll up my sleeves later this week to help them pack their donations.’