Microchannel plate photomultiplier tubes (MCP PMT) can work in a high magnetic field and have an excellent time resolution. The influence of the magnetic fields up to 4 T on the parameters of several MCP PMTs of different designs was investigated. PMTs with two, three and four MCPs were tested in magnetic fields. The tested samples have different diameters of MCP pores: 3.5, 6, 8 and 10 microns. Dependencies of the time resolution, the gain and the photoelectron collection efficiency on the magnetic field are presented below.