Abstract Hollow CdSe and CdS crystals with many striations parallel to the c direction on their side surface were obtained by the sublimation method. Proposed growth mechanisms for these hollow crystals are as follows: hollow CdSe crystals are composed of many c-needles grown on the lateral surface of an initial c-needle. The c-needles are developed from c-whiskers. These c-needles are united into a wall, leaving a cavity at its center. On the other hand, hollow CdS crystals are grown by a combination of several crystal walls extending from previously grown walls. Each wall is developed from an array of c-whiskers. As the result of such combination of crystal walls several cavities are left in the crystal.