Flow Shop Scheduling Problem (FSSP) has significant application in the industry, and therefore it has been extensively addressed in the literature using different optimization techniques. Current research investigates Permutation Flow Shop Scheduling Problem (PFSSP) to minimize makespan using Hybrid Evolution Strategy (HESSA). Initially, a global search of the solution space is performed using an Improved Evolution Strategy (IES), then the solution is improved by utilizing local search abilities of Simulated Annealing (SA). IES thoroughly exploits the solution space using the reproduction operator, in which four offsprings are generated from one parent. A double swap mutation is used to guide the search to more promising areas in less computational time. The mutation rate is also varied for the fine-tuning of results. The best solution of the IES acts as a seed for SA, which further improved the results by exploring better neighborhood solutions. In SA, insertion mutation is used, and the cooling parameter and acceptancerejection criteria induce randomness in the algorithm. The proposed HESSA algorithm is tested on wellknown NP-hard benchmark problems of Taillard (120 instances), and the performance of the proposed algorithm is compared with the famous techniques available in the literature. Experimental results indicate that the proposed HESSA algorithm finds 54 Upper bounds for Taillard instances, while 38 results are further improved for the Taillard instances.