The work stoppage will continue on Thursday and will take place again on May 3rd and 4th next week, mostly affecting flights to or from Barcelona, the airline's main hub.
Pilots are asking the airline, which belongs to British group IAG, to raise their salaries to the same level as their competitors and give certain benefits to those who will be transferred to bases abroad as the airline
“More than 120 pilots have left the company since the start of 2017, which gives an idea of the malaise in the group,” pilots' union SEPLA said in a statement.
According to Vueling, the strike will only affect 19 percent of flights, with 122 cancellations on Wednesday and 124 on Thursday.
The airline transported 29.5 million passengers in 2017, a record, and made a profit of €117.3 million ($143 million), 239 percent more than the previous year, according to its annual report.
The group employs 915 pilots out of a total of 3,089 employees.