The results of the investigation of uniform compression and magnetic field effects on phase transitions in Heisenberg ferromagnets CuRb//2Br//4 multiplied by (times) 2H//2O (T//c equals 1. 87K) and CuRb//2Cl//4 multiplied by (times) 2H//2O (T//c equals 1. 02K) are given. Magnetic susceptibility and magnetization measurements were carried out using modulation method on single crystals at pressure up to 10 kbar in the temperature range 4. 2-0. 4 K and the fields up to 500 Oe. For CuRb//2Br//4 multiplied by (times) 2H//2O the baric coefficient of T//c shift is equal to the dT//c/dP equals plus 0. 05 deg. kbar** minus **1. One observes nonlinear T//c increase for CuRb//2Cl//4 multiplied by (times) 2H//2O. The magnetic phasediagram is built. In a field applied along an easy magnetization direction there is a phase transition from a multidomain to a singlemagnetized phase but in a perpendicular field - from an angular to the collinear one. The results agree with predictions of the phase transition theory.