We present a cold atom gravimeter dedicated to field applications. Despite the compactness of our gravimeter, we obtain performances (sensitivity 42 µGal/Hz 1/2 , accuracy 25 µGal) close to the best gravimeters. We report gravity measurements in an elevator which led us to the determination of the Earth's gravity gradient with a precision of 4 E. These measurements in a non-laboratory environment demonstrate that our technology of gravimeter is enough compact, reliable and robust for field applications. Finally, we report gravity measurements in a moving elevator which open the way to absolute gravity measurements in an aircraft or a boat.Cold atom interferometer is a promising technology to obtain a highly sensitive and accurate absolute gravimeter. Laboratory instruments [1][2][3] have already reached the performances of the best classical absolute gravimeters [4] with a sensitivity of ∼ 10 µGal/Hz 1/2 (1 µGal = 10 −8 m/s 2 ) and an accuracy of 5 µGal. Moreover, compared to classical absolute gravimeters, atom gravimeters can achieve higher repetition rate [5] and do not have movable mechanical parts. These qualities make cold atom gravimeters more adapted to onboard applications like gravity measurements in a boat or in a plane. Cold atom gravimeters could thus be very useful in geophysics [6] or navigation [7]. In this context, cold atom sensors start to be tested on mobile platforms. An atom accelerometer has been operated in a 0 g plane [8]. An atom gradiometer has also been tested in a slow moving truck [9]. In this article, we present a compact cold atom gravimeter dedicated to field applications. First, we describe our apparatus and the technologies that we use to have a compact and reliable instrument. Then, we present the performances of the gravimeter in a laboratory environment. Finally, we report gravity measurements in a static and in a moving elevator.The principle of our cold atom gravimeter is well described in the literature [1] and we summarize in this letter only the basic elements. In an atom gravimeter, the test mass is a gas of cold atoms which is obtained by laser cooling and trapping techniques [10]. This cloud of cold atoms is released from the trap and its acceleration is measured by an atom interferometry technique. We use a Mach-Zehnder type atom interferometer consisting in a sequence of three equally spaced Raman laser pulses which drive stimulated Raman transitions between two stable states of the atoms. In the end, the proportion of atoms in the two stable states depends sinusoidally on *