" unsuspicious "

1: lacking in worldly wisdom or informed judgment;

  * e.g., " ... a happy-go-lucky, unsuspicious fellow who was easy prey for confidence men "

•  Synonyms : 

•  aw-shucks,

•  dewy,

•  dewy-eyed,

•  green,

•  ingenuous,

•  innocent,

•  naïf,

•  naive,

•  primitive,

•  simple,

•  simpleminded,

•  uncritical,

•  unknowing,

•  unsophisticated,

•  unsuspecting,

•  unwary,

•  unworldly,

•  wide-eyed

•  Antonyms : 

•  cosmopolitan,

•  experienced,

•  knowing,

•  sophisticated,

•  worldly,

•  worldly-wise