The aim of the study was to analyse the behavioural response in adult horses of various breeds, sexes and ages, to the toy hung in the box. 29 warmblood horses of Małopolski, Wielkopolski, Polish Warmblood and German breeds were studied. The horses were 4–14 years old. A plastic bottle was used as a toy. Each horse was tested and filmed for 15 minutes on two successive days. The following parameters were determined: (A) total length of play time excluding breaks, (B) number of breaks in playing, (C) total length of breaks in the play, (D) the time left to the period of 15 minutes when a horse was indifferent to the toy. Least square analysis of variance was performed considering factors of the breed, sex and age of the horses, as well as the day of the test. Correlations of parameters between the two days of the test were determined. The breed and age factors did not significantly influence the parameters. Stallions stopped playing long before geldings. The total length of play time was higher on the first day compared to the second day of the test (24.8% and 14.9% of the test time, respect ively). The correlation of the total length of the play time between two days of the experiment was significant (r = 0.38). The results allow the conclusion that the toy hung in the box has a weak effect on improving the horse’s welfare