The utility model relates to an unequal venturi in convergent flaring angle restraints and CFB absorption tower thereof belongs to the environmental protection technology field. This venturi restraints including a central venturi, a plurality of marginal venturi, overhead gage and lower baffles, center venturi is located the center that venturi restrainted, edge venturi evenly distributed is around central venturi, flaring angle and each imbalance of convergent angle of the intrafascicular venturi of venturi, venturi's convergent end diameter, the change of choke diameter are matchd rather than the convergent angle, the top of the entry structure of CFB absorption tower bottom is provided with foretell venturi and restraints. The utility model provides a pair of the flow field was even, stable in unequal venturi in convergent flaring angle restraints and CFB absorption tower thereof can effectively realize the desulfurizing tower, and implemented simple structure, the resistance that does not increase the desulfurizing tower and investment.