Daily movements in a population of the spider crab Maja crispata were studied in the northern Adriatic Sea. The sex ratio of males to females was 3:2, with males reaching a maximum carapace length of 91 mm and females a maximum of 74 mm. M. crispata was most abundant on the bottom of the boulder field than in any other habitat. The seven studied specimens had non-directional movements in unrestricted areas and stayed mostly on the rocky bottom at depths ranging 0.8-3.5m. The maximum distance from the starting point, reached in 9 days, was 16 m.