Standard group searching optimization（GSO） is a swarm intelligence algorithm for high-dimensional function optimization.It is simple and efficient

and easy to implement.In order to enhance its convergence speed as well as precision

an improvement on this method is presented.Inheriting the framework of"producer-scroungerranger" of GSO

the improved GSO（iGSO） introduces the strategy of maximum descendent direction to the behavior of the so-called producer.In each iteration

the producer searches not only according to the direction of itself

but also according to the maximum descendent direction.Tests are carried out through 23 standard test functions on GSO and iGSO independently

the results shows iGSO method is prior to GSO.