Spectrophotometric observations of OQ 208 over the time period between March 1985 and February 1991 are presented. It is found that the H-beta flux varies strongly over the period of observation. The peculiar profiles of the Balmer lines are variable, and their variations make it possible to place some unambiguous constraints on the broad line region structure. Possible models capable of explaining the observed properties of OQ 208 in a simple way are examined, and it is suggested that the most plausible scenario to explain the Balmer line emission involves a system of clouds accelerated by radiation pressure in a biconical configuration plus an additional contribution from a cloud component that is either spherically symmetric or confined within a thick cylinder.