The present invention relates to plasmids whose hosts can be Escherichia coli and some kinds of yeasts, namely, shuttle vectors, as well as to processes for producing said plasmids. There are provided in the present invention (1) plasmids containing an autonomously replicating sequence of Candida maltosa, Leu 2 gene derived from Saccharomyces cerevisiae and an ampicillin resistance gene and (2) plasmids further containing a tetracycline resistance gene as well as the genes described in (1).The plasmids (shuttle vectors) of the present invention can be utilized as follows. A useful foreign gene is inserted into plasmids of the present invention; using the resulting new plasid, Escherichia coli is transformed and cultured in order to obtain the plasmid in a large amount; and using this plasmid, Saccharomyces cerevisiae or Candida maltosa as a host is allowed to produce useful substances such as hormones and enzymes on a large scale.