An eight year veteran at the firm, Mr Catto is currently a member of the Atkins executive board head by chief executive Keith Clarke.
He has been at the firm for five years and has been group managing director of the Design & Engineering Solutions division since it was formed back in April 2005.
Mr Catto will take up his new role on 1 December and will replace outgoing Hyder chief Tim Wade. He was due to leave at the end of next month but will now stay on until Mr Catto joins.
Mr Wade, who will be 64 in August, will step down after more than 17 years at the business. He will be joined later this year by finance director Simon Hamilton-eddy who leaves after 16 years at the group.