The 2009–10 season was Alkmaar Zaanstreek's 43rd competitive season, 12th consecutive season in the Eredivisie and 43rd year in existence as a football club.

In addition to the domestic league, AZ participated in this season's editions of the KNVB Cup, Johan Cruyff Shield and UEFA Champions League.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Players may hold more than one non-FIFA nationality.

Source: [1] Source: Competitions AZ, as Eredivisie winners in the previous season, played against Heerenveen in the 2009 Johan Cruyff Shield, who themselves won the KNVB Cup.