The 29-year-old Finn has been a key member of the Amsterdam outfit’s XI in recent times, but his future with the Eredivisie giants appears to be unclear.
Moisander’s current contract is due to expire at the end of the season, which has alerted Spurs.
The Londoners are looking into a cut-price move in the hope that Ajax may relent and sell their man rather than lose him for free next summer.
Mauricio Pochettino is understood to have concerns about his defence – which has already been breached 11 times in eight Premier League games this season – despite the signing of Federico Fazio and the promotion of Younes Kaboul to captain.
Reports suggest that Moisander himself is ready to leave Holland, which has buoyed Spurs.
The Londoners have done much business with Ajax in recent seasons, with both Jan Vertonghen and Christian Eriksen having swapped the Amsterdam ArenA for White Hart Lane.