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This paper focuses on the scheduling problem of minimizing makespan for a given set of jobs in a two-stage hybrid flowshop subject to a product-mix ratio constraint. There are identical parallel machines at the first stage of the hybrid flowshop, while there is a single batch-processing machine at the second stage. Ready times of the jobs (at the first stage) may be different, and a given product-mix ratio of job types should be kept in each batch at the second stage. We present three types of heuristic algorithms: forward scheduling algorithms, backward scheduling algorithms, and iterative algorithms. To evaluate performance of the suggested algorithms, a series of computational experiments are performed on randomly generated test problems and results are reported.Keywords Scheduling · Heuristics · Hybrid flowshop · Product-mix ratio · MakespanWe consider a scheduling problem in a hybrid flowshop (HFS). In a typical HFS, there are K serial workstations and there are multiple parallel machines at one or more workstations. This paper focuses on a two-stage hybrid flowshop in which there are multiple identical parallel machines at the first stage and a single batch-processing machine at the second stage. In the HFS considered in this study, there are two types of jobs, and a given product-mix ratio of the two job types should be kept in each batch at the second stage. Also, jobs arrive at the first stage dynamically, that is,

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